Skip to main content

Full text of "Page 6 Magazine Issue 85"

See other formats


DID YOU KNOW! 



We still have the very best FD library 
far the Atari. Classic 

There are over 400 disks available 

Many disks are only £1,50 each 

Collections and special sets are even cheaper 

EVERY PURCHASE OF A PD DISK 
HELPS TO SUPPORT THE MAGAZINE 

DID YOU REALISE? 

We still have the entire ST library available 

There are over 1 ,000 disks 

Disks are only£l each 

We will send you details on request 

KEEP SUPPORTING US 
AND WE WILL KEEP SUPPORTING YOU 




Issue 85 - Autumn 1996 



£2.50 



FOR THE ATARI CLASSIC 




© LEAGUE TABLE 

Follow your favourite teams 
%^ ° SUPER FILE READER 

^ A neat simple way to read doc files 



^rTSBn? ° ^HORT HISTORY OF COMPUTERS 

■^J^jj^lJJj ^J— Celebrate the 50th anniversary 



of the computer 



M WER SCM m 



HOW TO PLAN 
YOUR VACATION 
ON THE INTERNET 



Billy Sob's j£*<* 

W« HiTT A Hon*? TM* Attlt*4*l 

B: 



W^i hkn.na ui^i thrift 

— - '■ | 



PLUS ... SUPEBCIRCLES .„ AUTOMATIC PROGRAMMING ... TURBO TUTORIALS ... THE TtPSTER ,. AND JU0fi£< 







THanks 



hes Effingham, puts ft all. together and fills 
up the gaps but the real thanks goes to the 
following who made this Issue passible 

Sandy Ellingham who takes care of all the 
office work, advertising and mall order 

For tJveir contributions this issue 



James Austin 
WU JForter 
John Tanner 
John Robinson 
John Harrington 
Allan Palmer 
Joel Goodwin 



John Foskett 
HSWood 

Austin Hill man 
James Matthrick 
Gavan Moron 
John 5 Davison 



APOLOGIES 



1 am still extremely poor in acknowledging 
contributions so I apologise to everyone 
who has sent In stuff and. drought it has 
gone through the wnrmhole. The Intention 
to reply t« everyone is there but the time 
seems to drift by. If you have not heard, 
thank you and keep watching the mag. you 
might be surprise a. 

HOW IT'S DONE 

PAGE B shows Just What you can do With your Atari. 
NEW ATARI USER has always been created entirely with 
Atari equipment, Initially on the XL but more lateiv with 
b. Mega ST and other stuff, who needs PCs or Mackl 
Hardware includes a Megi ST2 [upgraded to 4Mbj. 
SMI 25 Monitor. Supra 30Mb Hard Disk, a HP LaserJet 
Di. Citizen 12-4D printer. Philips CM8S33 monitor, ' 
1 30XE, a couple of 1050 disk drives. HSO interface, NBC 
8023 printer. Principal software used is Pretext and 
Fleet Street Publisher 3.0. Other software includes Ker- 
mtt. TarfTailt Turbo Basic and various Custom written 
programs on the XL/XE, Articles, submitted on XL/XE 
disks are transferred across to the ST via TARTTALK. 
Programs are coded on the XE and printed out directly 
for pasting In after (lie typesetting Is completed. All 
major editing Is done with Pretext and pages are laid out 
with Fleet Street Publisher, Each page Is output directly 
from Fleet Street to a HP Laserjet 111 which produces 
finished pages exactly as you see them. Ail that Is left te 
to drop In the listings and photos. 
Well, it's not <-[Ulte as easy as that but you get tile Ideal 



Inspiration 



I just started this issue several monihs ag 
sol haven't got a clue what I was listening to 
at thai time. As I type this Celine Dion is 
playing but thai is a Utile unusual these days 
as most of my listening has been of Native 
American Music Nothing riew - 1 can't afford 
it - only things that I have mentioned in past 
issues. Oh, I almost forgot - Ann O'Driscoll 
very kindly sent me a CD calied A Woman's 
Heart U and pretty good It is too u/iiJ\ a 
couple of tracks thai iin?re already favourites 
from Dolores Keane and Maura O'CannelL 
Your kindness is very much appreciated, 
Ann, In what is becomkyj a gloomier world. 

CONTRIBUTIONS 

Without contribution* from its renders, NEW 
ATARI USER Would not be possible. PAGE t; 
welcomes and encourages its readers to sub- 
mit, articles), programs and reviews for publi- 
cation. Programs must be submitted on disk 
or cassette, articles should wherever passible 
be submitted as text files on disk. We seek to 
encourage your participation and do not 
have strict rules for submissions. If some- 
thing interests; you* write a program or arti- 
cle and submit itl 

COPYRIGHT 

All original articles, programs and other material in 
NEW ATARI USER remain the copyright of the au- 
thor as- credited , All unctcdited material Is copyright 
PAGE 6. Permis-sion musl lie sought hy anyone 
wishing to republish any matcrtalT Whilst we take 
whatever steps we can to ensure the accuracy of 
articles and programs and the cesnteniK of advertise- 
ments, PAGE 6 cannot be held liable for any errors 
or claims made by advertisers. 

ATARI fTMJJ la ft registered trademark ft! ATARI CORP. All 
reference, should be *« naiad. MEW ATARI USER I* an 
independent publication and has no connection wilfri Alan or 

with any other company or publisher. 



^ 



Editorial address: P.O. Box 54, Stafford, ST16 1DR, ENGLAND Tel. G17&5 241153 
Editor & Publisher. Les Ellingham - Advertising.- Sandy Ellingham 
Page layout by PAGE 6 - Printed by Dolphin Press, Fife, Scotland 01592 771652 
HEW ATARI USER Is published bi-monthly on the last Thursday of the monlft prior to cover dale 

Page 6's New Atari User 



PAGE 6 PUBLISHING'* 

ATARI 

'The Magazine for the 
Dedicated Atari User' 



ISSN No. 0958-7705 




REGULARS 




EDITORIAL 


4 


MAILBAG 


8 


THE TIPSTER 


32 


CLASSIC PD ZONE 


47 


CONTACT 


IBC 



STILL A WHILE 
TOTHENEXT 
COPY DATE BUT 

PLEASE 
CONTRIBUTE 

NOW! 



CONTENTS 

Issue 85 - Autumn 1998 



PROGRAMMING 

SUPER FILE READER 5 

A neat simple ujay to read doc files 

SUPERCIRCLES 13 

Don't put up with imperfect circles any mare! 

LEAGUE TABLE 16 

Follow your favourite teams 

AUTOMATIC PROGRAMMING 22 

Learning about J?etum Key Mode 

TEST CARD 29 

Get the best picture from your TV 

PMG PROGRAMMING TIPS 31 

TURBO TUTORIALS 35 

DISK DIRECTORY MOVER V.H 40 

An update an a great program 

FEATURES 

A SHORT HISTORY OP COMPUTERS 24 

Celebrate the SOth anniversary of the computer 

USER VS PROGRAMMER 42 

Bringing the two together 

JOURNEY INTO CYBERSPACE SO 



COPY DEADLINE FOR NEXT ISSUE - 5th JANUARY 



MAGAZINE ONLY 

Annual subscription rat«s (6 issues) 

UK £15.00 

Europe (Air Mali) E1T.00 

Elsewrwe (Surface) CI 7.00 

Elsewhere (Air Mail) E23.0O 

Overseas rates reflect only the difference in 
postal costs 

Please make cheques payable 
PAGE e Publishing, P*0, 



DISK SUBSCRIPTION 

A disk containing ail el the Et-btt program* from aach 
iaaua at NEW ATARI USER is wail able sillier separate- 
ly ar an subscription. Single pric* E2.8S p*r disk, a 
disk Subscription saves you almost £fl « yaar. Sub- 
scription rata* (6 is*u*4) 

UK £25.00 

Europe £32.00 

Elsawhara (sea) £32.00 

Elsawhara {Air) £42.00 

to PAGE 6 PUBLISHING and send to 
Box 54, Stafford. ST16 1DR 



TrditoriaC 




THE FINAL COUNTDOWN 



At last, another Issue of NAU pops through your door. Thank you for keeping the Faith 
and not hassling me too much. 
Sadly all the good Intentions for this year have gone to pot as the currcnL government 
continues the previous government's policy of trying to destroy those who don't have conven- 
tional Jobs. All this business about controlling inflation merely sacrifices people like me on the 
altar of those who already have most of the money. Increases in Interest rates, and thus 
mortgage rates, stops people spending money which makes it more and more impossible for 
people like me to make a Irving. As you know I set aside a number of weekends this year to 
commit to NAU but because each craft fair that I have done this year has been worse than last 
year I have had to use each of those weekends to do more fairs In order to be able to stay 
afloat. That means, of course, no time to complete the mag. This month {October) has been so 
bad that it is almost certain that 1 will now have to And a conventional part-time job working 
nights, or whatever, in addition to the craft work, That of course means even less time. Cod 
knows how I will cope. 

It seems obvious that I need to give you, the faithful supporter of NAU, a commitment that 
you will get the magazines you expect and whilst I cannot guarantee each Issue will be on time 
I can guarantee that there will a certain number of future Issues. 1 have therefore decided to 
begin the final countdown for Page G/Hcw Atari User. There will be six more issues of the mag 
after this one and then I will call It a day. It is unlikely that each Issue will be on the 
bi-monthly deadline but you will get the mags you expect. We are already the longest 
published Atari magazine and my aim now is to be the first Atari magazine to close publication 
without its readers losing money on their subscriptions. As your subscription falls due you will 
be asked to renew only for the number of issues remaining. 

As each issue is published It will become more and more difficult for me financially since 
there will be less and less renewal income. I therefore ask you to please ensure that you renew 
your subscription for the remaining Issues, even if you no longer use your machine as much as 
you used to. Your commitment thus far has been much commendable, please now stick with 
us to the end. It Is vital that we receive your continuing support. 

Here's what you can do; 

• Renew yow subscription when requested and know that you wtU get the rest 
of your mags 

• Continue to buy a Jew PD disks now and then as this £s our only means now 
of additional support 

• Make sure that you contribute to the remaining issues by writing tetters, 
articles or sending programs 

I am committed to giving yov six more issues of NAU to take us up to the millennium, 
but I need your support to do that. Let's all slick together and bow out gracefully, knowing that 
we created something great over all these years. 



Les TMnghaffl 



PROGRAMMING 



SUPER 

FILE READER 



Page 6's New Atari User 



The Super File Reader (SFR] Is a docu- 
ment file reader in Turbo-B ASIC (XL/ 
XE computers only] that 1 have writ- 
ten to enable quick and easy reading of docu- 
ment files In a properly presented fashion 
on-screen, 
SFR has several features which set it apart 
from most other programs of Its type. Flrsdy, 
it loads in as much of a document as It can in 
one go. so going some way to removing the 
need to keep the disk In when reading the file. 
Secondly, It automatically formats all docu- 
ments during the reading process to cater for 
word-wrap and to ensure correct presentation 
when the files are displayed on-screen. And 
thirdly. It allows you to go back and forth at 
leisure through your documents, so you can 
go back and look at anything you might have 
missed or want to read again. 
Although all references made in these in- 
structions are to DOCUMENT files, ft is also 
possible to load In and read other files if 
desired - however* it may be preferable to use 
a wurd processor program [such as TextPRO) 
for this purpose. 

SFR has a text buffer of 26, 500 bytes 
(approx. 26kB) which will allow document 
files of up to 2 12 sectors in size to be loaded 
in one pass - In practice this means that most 
document files will load in one go, however 
flies larger than this can a till be loaded in 
sections using the special oversize file 



by James Austin 



routines built into the program, 

I hope that you find SFR to be a useful 
program. Not exciting I know, but It was writ- 
ten to satisfy a need that I had and so it may 
well prove useful to you too. 



THE MAIN MENU 

All of SFR's operations are controlled 
through Its main menu, which is displayed 
automatically at start-up. It displays 4 diffe- 
rent options: 

[1] Read in tile 
[2] Display tile 
[3] Disk Directory 
[4J Exit SFR 

To access these options, press [1), [2], [3| or 
[4 J respectively. I will go through each In turn, 
starting with the main two options - 11| and 
12], 

Options 1 1 ] and |2] allow you to load in and 
display your document files respectively, A 
document file must have been loaded In pre- 
viously and be resident Jn memory before op- 
tion (2] can be accessed. 



Page 6's New Atari User 






LOADING IN DOCUMENT FILES 

Press ( 1] first of all. The main screen will 
clear, and the message READ WHICH FILE? :' 
Is displayed. This Is a prompt for you to enter 
the name of the document file you wish to 
load In, so enter It here and press [RETURN], 
No device should be entered. Wildcards are 
not supported. Remember to have the proper 
dtsk In the drive before you hit the key. since 
the program Immediately begins to scan the 
directory sectors on the disk to locate your 
file. If your file Is not on the disk, then the 
prompt NO SUCH FTLE ON DISK! 1 1' will 
appear, and you will be returned to the origin- 
al prompt to try again. 

if your file is found, then, the program will 
immediately begin scanning that file's sectors. 
DO NOT TAKE THE DISK OUT AT ANYTIME 
DURING THE LOAD!!! - the program uses a 
machine code routine to access the Device 
Control Block and Internal Disk Handler 
routines and, although nothing nasty should 
happen, don't try it! You could crash the 
computer or even corrupt your disk In so 
doing, 

[f the pT^mpt TOO LONG - FORMATTING 
PART LOADED.,.' appears, then the file Is too 
long to load into the buffer in one puss. Bear 
this in mind for later on when I will explain 
how to load in oversize files. If the file suc- 
cessfully loads In one pass, then the prompt 
FORMATTING FILE-..' will appear instead. 
The program is now formatting your docu- 
ment The length of time this will lake will 
depend on the length of the file you have 
loaded, also whether it Is a true document or 
not If you load a non^document file then you 
may well be waiting a LONG while as the 
program will have a bigger Job on its hands 
than with a document file. Otherwise, you 
should not be kept waiting too long. Once this 
has been accomplished you will be returned 
to the main menu. 



DISPLAYING DOCUMENT FILES 

Now press [2]. The screen will clear and the 
first page of your document displayed on the 
screen. Notice the prompt 'PAGE K OF x r 
which appears at the bottom of the screen 
while this is being done - this tells you what 
page you are currently on, as well as how 
many pages there are in total. Once the page 
is completely shown on-screen, this is re- 
placed by a small menu: 

4 - BROWSE ? CHOOSE PAGE ESC TO EXIT 

Pressing [+] will display the next page in the 
sequence (if there is one), while [-] will move 
back to display the previous page. Pressing 
[ESC]apc will return you back to the main 
menu. If you press [PJ then the screen clears 
and the message 'NEW PAGE #;' appears. 
This is a prompt to choose which page you 
wish to go directly to. Enter the page number 
of your choice and then press [RETURN]. Only 
valid page numbers will be accepted. The 
appropriate page will then be displayed and 
you will be returned to the above menu. 



OVERSIZE FILES 

Now on to the subject of reading in oversize 
files. To read the next part of the file, press 1 1 ] 
again - the message CON1INUE LOADING 
SAME FILE Y/N ?' will be displayed on- 
screen, if you press [Y] the next segment of 
the file will then be loaded in, formatted and 
displayed in the same way as described pre- 
viously. If you press tNJ, then the load fs 
terminated and the prompt to load an alter- 
native file comes up. !t should be noted that 
the previous part of the document file is lost 
when a new part Is subsequently loaded in, so 
you will need to load the file from scratch to 
view previous pages again. 



6 



Page 6's New Atari User 



SFR will cope with as many additional parts 
of a document as are required to load the file 
in completely: It will also ensure that words 
are not broken between segments of a file but 
are Instead presented In full on-screen when 
the next part Is subsequently loaded in. 

DISK DIRECTORY OPTION 

Option |3| allows you to obtain a directory of 
the files on a disk in the default drive (usually 
drive H. Ensure that a disk is in that drive 
before accessing this option. 

The directory will be scanned and the files 
on the disk displayed in two columns on the 
screen. If there are too many files on the disk 
to display on the one screen, the message 
'CONTINUE READING DIRECTORY Y/N T 
will appear at the bottom of the screen. Press- 
ing |Y] at this point will clear the screen and 
display more of the directory, while pressing 
any other key will exit back to the main 
menu. If the files do all fit on the one screen 
then vou will be asked simply to press a key 
to exit back to the main menu. 

EXIT SFR 

This Is the final option available from the 
menu, accessed by pressing [4]„ When this 
option is accessed, the prompt. "DO YOU 
WISH TO EXIT Y/N T will be displayed. Press- 
ing [Y] will exit this program and place you in 
the Turbo-BASIC editor. Any other key will 
return to the main menu. 



PLEASE NOTE... 

SFR automatically Inserts Inverse -asterisks 
into your document file to format the pages so 
that they appear properly on-screen. This 
means that It is not possible to Include in- 



verse-asterisk characters In your documents, 
since this would corrupt the pagination and 
cause parts of your document to disappear. 
The program therefore converts all- inverse - 
asterisks that it finds when loading the docu- 
ment Into "normal" (non-lnversed) ones. 



A BUG 
IN TURBO-BASIC? 

Now here Is a question for all experienced 
readers out there. Is there a bug with the 
INSTR/UlNSra commands in Turbo-BASIC? 

10 DIM TEXT${3):TEXT$-"*@" 
20 LETLOC-INSTR(TEXT$r"\1) 

I found With this example that LOG equals 3, 
not 1 as I would have expected. What seems 
to be happening Is that the command Is "mis- 
sing" the first asterisk in the string, possibly 
because it is beginning the search from the 
SECOND character in the string rather than 
from the first one as I wanted? Change line 20 
to: 

20 LET LOC=INSTR(TEXT$ f "*",0) 

and LOC becomes 1, ihe answer that I 
thought the first example would have given 
met 

I wasted a LOT of time with this when writ- 
ing SFR Is there a bug? 



FINALLY 

If you experience any difficulties with using 
the program, dont hesitate to contact me at 
19 Ctive Road, Bobbing, nr. SiMngboume, 
Kent. MEW IPJ, ENGLAND, and I will try to 
help you out as best I can. 



Page &s Neui Atari User 






Mailbag 




DID YOU 
WRITE? 



Yet again we have one 
of those issues where 
only a few people de- 
cided to write in. J know 
the copy date for this 
issue was supposed to 
he really close to the 
date you received your 
last mag, but don't let 
that stop you writing. 
Write to us at any time, 
if your letter doesn't 
make it into the next 
issue it wilt go in the 
one after. We need your 
letters, they really help 
us out and let us know 
you are stiR interested. 

Les Ellingham 



a 



WHICH PRINTER? 

Reader WIIJ Porter from 
North Ching/oni has a p mt 
km that he would like your 
help with, which might also 
be a good s tararig point for an 
article: 

Tor many years 1 have vised 
an Atari 1020 Printer/Plotter, 
but now It Is not possible to 
obtain supplies and I would 
like to output text from disks 
such as Home Filing Mana- 
ger. The problem Is how do I 
modify the disk to output to 
my Epson printer? 
The problem also applies bo 
other disks which L have pur- 
chased from Page 6 Library 
In past years. Perhaps one of 
your more expert readers 
may be able to answer this, 
or possibly write an article on 
the subject as I am sure that 
I am not the only reader with 
this problem" 

t I don't know about Home 
Filing Manager which prob- 
ably has Its own method of 
saving fUes but I can't see 
why you should haue prob- 
lems with Page 6 Library 
disks which have not be cre- 
ated for specific printers. Of 
course you may be talking 
about programs that were 
specifically written far the 
1 020. On ordinary DOS files 
you may like to try using DOS 
Page B's New Atari User 



to dump the files to your 
Epson. All you do is call up 
DOS and use the Copy option 
iO with the parameters flle- 
name.ext,P: urhfch mill dump 
the file filename. ext (of course 
use the name of the file you 
want to print) to your printer. 
You won't get any formatting 
but at least you'll get printed 
copy. There are many other 
ways of getting printed copy 
s uch as saving text vers ions 
q/'Jftes to dis k and then load- 
ing them ftito a mord proces- 
sor. Maybe this can be done 
with Home Filing Manager. 
Perhaps someone can check 
this out and unite into Mail- 
bag or put it together as an 
article. 



MORE 1050 PROBLEMS 

John Tanner has a problem 
flvat the more practical hard- 
ware buffs cart probably help 
mith; "For many years, my 
family has enjoyed the use of 
our original purchase 80CXL 
and the second 1050 which I 
acquired a few years ago. 
The problem? A few weeks 
ago when the machine was 
taking a rest from the chil- 
dren, but was left powered 
up, I noticed a strange smell, 
then 1 saw a thin stream of 
smoke rising from the second 




105O. The drive Is fitted with 
some sort of enhancer chip 
set (In the U9 socketj. Exami- 
nation of the circuit revealed 
that two sma]] capacitors 
(C65, C66?) immediately tn 
front of large blue capacitor 
CSS and between TP 1 4 and 
TP1S were completely burnt 
away, and had slightly dam- 
aged C66. J also noticed that 
CR1S and CR16 (2 diodes?) 
between the large capacitors 
C71 and C68 are both swol- 
len and one Is cracked. 

Is It likely that the replace- 
ment of these components 
would restore the disk drive, 
or could some underlying 
fault have caused the over- 
heating? Advice on repair 
would be most welcome as 1 
have no service manual /in- 
formation on the 1 050, 

ff repair proves to be not a 
practicable solution a "wan- 
ted - ad for a replacement 
drive would be the answer, as 
life with the single drive is so 
frustrating! 

Incidentally both drives did 
read and write satisfactorily, 
although some disks seern to 
have a definite preference for 
one of them, however both 
give trouble with formatting 
with failures appearing to 
occur on the final tracks, Is 
there a simple reason for 
this?" 



m AND PROGRAMMING 

John nouf charujes tack and 
fancies a bit of programming,. 
His letter continues: " Now for 
something completely diffe- 
rent, I would like to try my 
hand at programming our 
Atari (machine code that is], 
so 1 need some literature on 
the subject, including the 
memory layout of the 
machine. If there's someone 
out there who could help, I'd 
be eternally grateful. 

Finally, a few years ago 1 
began procedures to get a 3 Mi" 
disk drive interface from 
Derek Fern, buy for varioua 
reasons at the time 1 let the 
matter drop, f now would like 
Id purchase one of these in- 
terfaces if they arc available." 

f Thanks for writing, John, 1 
can't help with the 1050 prob- 
lems (way above my head!) 
but I am sure that fcliere are 
readers u>ho can. As to trie 
machine code writing you will 
have to get hold of some 
second-hand books as there 
is nothing currently in print. 
Best bet is for someone with 
some surpfus books to get in 
touch with John direct You 
can glue him. a ring on 01545 
580025. Of course you might 
be able to help with the disk 
drive pmblem by talking to 
him but (f you do please also 
Page &s New Atari User 



write to Mailbag as 1 am sure 
that the solutions will be of 
interest to other readers. 



DIY BINDERS 

John Robinson up in. Cumbria 
has some more suggestions 
for making your own binders 
for NAV which he feels inight 
be cheaper than Eddies 
Jones' method tn Issue 84. 
"Again, use the Rexel Budget 
binder number 13428 and 
obtain a pack of Graflx A4 
punched pockets, usually 
sold In 10s but currently 
available from Asda and dis- 
count stationers for about £1 
for 40. Take a pocket and fold 
it lengthwise, then cut in two 
with a very sharp knife. Dis- 
card the plain half. Fold the 
half with the white punched 
strip attached, and cut that 
In half again. The result will 
be two transparent pieces 
152mm long by 1 1 5mm deep, 
each of which will hold one 
copy of NAU. Split the bottom 
of the pocket, to allow the 
two "pages' to open out. Nejrt. 
carefully mark the cover of 
your magazine 29mm from 
the top and 29mm from ihc 
bottom using a soft pencil. 
Obtain a UHU glue pen, and 
apply the gum to one inner 
side of the plastic (top, mid- 

9 



*i 




die and bottom, then the 
outer edge In an E shape) 
and press the back of the 
magazine cover firmly onto 
this. Glue the other half, 
attach to the front cover and 
there you have it a "see 
through 1 means of utilising 
the spring dips in your 
binder. 

Two tips - the second cut to 
halve the spine of the pocket 
will cut through a hole which 
Is exactly In the centre of the 
punched spine - always en- 
sure this half hole Is at the 
same end of your mags, in 
the interests of neatness, and 
always use a very sharp knife 
to cut the pockets - they are 
tougher than you think and 
also very slippery I. Each bin- 
der holds six copies, very 
handily." 

T Many thanks, John, It is 
always helpful to share 
ideas. In closing John has 
asked, if anyone has a copy of 
the SYNCALC spreadsheet 
they no longer want as he is 
desperate Jar a copy. If you 
send ft in to us, we wiR pass 
it on. 



KEEP YOUR ST! 

John Honing ton is one of 
those people who 'upgraded' 
to a PC but who has now 

10 



Jbund that his STcan still he 
put to good use. He explains - 
"A while back 1 bought a 
batch of ST PD stu ff from 
you. My reasons were mainly 
selfish - to get my three boys 
to leave the PC alone so 1 
could use ttl My lads are all 
aged under 8 and the GEM 
Interface Is not as familiar to 
them as Windows 95 so Ini- 
tially they were all reluctant 
to use the ST, but on Sunday 
[ finally found the time to set 
the ST up and go through the 
dozen or so disks you sent 
me. The inevitable result was 
that the three ended up fight- 
ing over who had command 
of the Joystick s . in between 
punch-ups it kept them 
amused for about 6 hours 
which means ] have already 
had my money's worth. 

The two young "uns (aged 4 
and 6} particularly enjoyed 
the Mr. Potato 1 Lead and 
Spitting Fish games whilst 
the eldest enjoyed PacMan 
which, so far as I can see, is 
indistinguishable from the 
arcade version. 

Okay, some of the software 
is Incredibly rudimentary - 
the arithmetic testa on one 
disk are just text and random 
numbers - but for the infant 
school generation it (a) does 
not seem to matter too much 
and [b) it's helpful to them In 
their work. 

Page B's New Atari User 



So, as soon as we have 
sucked this lot of disks dry 
J'll be ordering another batch. 
The only drawback with the 
ST Is the lack of a hard drive 
- It would be great if the files 
were just one [double) click 
away from running once the 
ST Is switched on. So, 
although it defeats the object 
of encouraging the kids to 
use their own computer and 
not my PC, I downloaded an 
Atari ST emulator from http:/ 
/pacifist, fa taldeslgn, com/ 
this week. I can tell you It 
really was eerie seeing the 
GEM desktop on my PC. I'm 
not entirely sure I have got it 
up and running property yet 
as I tried an old favourite 
game of mine called Gridiron 
and It said the disks were un- 
readable. 1 haven't had the 
time to try them out on the 
ST yet to see whether the 
disks are merely unreadable 
on the PC's disk drive or 
genuinely damaged, 

There are, of course, emula- 
tors for the Atari Classic and 
I downloaded the files for that 
too. The drawback is that 
although I have a 5 W disk 
drive on my PC, it won't read 
Atari floppies- I've not read 
the documentation thorough- 
ly yet but it appears there Is 
some cabling needed to hook 
up my Atari disk drive to the 
PC, There are some Atari 




Classic 'disk Images' avail- 
able for download from the 
Web, which means you can 
run those directly from your 
hard drive, but most of the 
games 1 want to run are 
strategy games {Rails West J. 
M"U"L*E\ Seven Cities of 
Gold) and not the arcade dit- 
ties that most people seem to 
run of their Atari. 

1 know your correspondents 
have covered emulators In 
previous issues but It might 
be an idea if those people still 
supporting the Atari Classic 
were to put together an emu- 
lator package' for lazy thickos 
like me and publicize it 
through your magazine." 

T Bet you are now glad, that 
you didn't sell your ST for a 
pittance at a car hoot sale tike 
so many other people! The 
obvious answer to the lack of 
a hard drive for your ST ts to 
buy one! Believe it or not you 
can still purchase a hard 
drive for the ST fat least you 
could a couple of months ago). 
They are not quite as cheap 
as those available for the PC 
but are considerably less that 
the £300/£400 you had to 
pay for the Supra drives, Be- 
cause the ST is still widely 
used in music environments 
there is quite a demand for 
upgrades and one of the 
music mags recently reported 
that The Upgrade Shop in 



Macclesfield can supply some 
amazing hardware upgrades. 
They state that an internal 
hard disk drive can be added 
to art STEfor£100far a 
1 70Mb model going up to 
£160 for 720Mb. You can fit ft 
yourself or haue it fitted for 
youfor£15 plus £7 courier 
collection arid delivery in each 
direction. A couple of years 
ago The Upgrade Shop were 
also advertising external hard 
drives for the ST (at a much 
higher price, although this is 
sure to have come down) and 
these may still be available. If 
you are used to using a PC 
hard drive then, you might 
thihJc that 1 70Mb ts a rather 
small drive but the PC is in- 
credibly inefficient in data 
storage and 1 70Mb on the ST 
is more than you ore ever 
likely to need, I have a 20Mb 
hard drive and it copes ade- 
quately with all J hone to do. 
Just think, with 170Mb you 
can store something like 230 
single sided ST disks! 
If you want to get more de- 
tails give The Upgrade Shop a 
ring on 01 625 503448. 



RANDOM NOTES 

Allan Palmer has promised to 
organise some of his ramh- 
hngs into an article for us 

Page B's New Atari User 



(committed you nou>. Allan!) 
but in the meantime has a 
few random nates of tnten?sL 
"Any information on Atari 
Simulators for PCs would be 
more than welcome: hopeful- 
ly some of our readers can 
elaborate more. 
- Kevin Cooke's letter In the 
la3t issue had plenty of in- 
teresting comments, 
although as you'd probably 
guess from my last letter, I 
disagree with Kevin that the 
Internet/World Wide Web 
has given him limited suc- 
cess. You need to put a bit of 
effort Into a search for what 
you need and be specific, 
"Sick Building Syndrome" 
would have been a better 
search text than just "SBS" 

Finally could you please note 
my new e-mail address which 
is now Allan_Palmcr@big- 
fooLcom" 

I Many thanks Allan, your 
e-mail address should now be 
correct tn our Internet Con- 
tacts column. Your paint 
about searching on the Inter- 
net is well taken although I 
continue to have the odd dab- 
ble and I still can't get to grips 
with fisfintng searches* The 
problem is that all of the 
search engines seem to use 
different criteria for their 
search with some requiring in- 
verted commas around a 

11 







phrase, others needing under- 
lining between linked words 
and yet others needing plus 
signs on words to be in- 
cluded. It is okay if you have 
unlimited access to the Inter- 
net at home or at work (even 
betler if you don't pay the 
phone bill]} but when you 
have a hour at the library, it 
is difficult to learn all the dif- 
ferent ways of using various 
programs. Perhaps. Allan, 
you or some other reader 
could do us a short article an 
the best way to use uartous 
search engines, liStnG some 
sort of practical example? I 
know that there are various 
books around that may give 
you this information hut it 
would be handy to have it In 
one place. Incidentally Staf- 
fordshire Libraries are now 
hooked up to the Internet and 
uery reasonably priced atjust 
£1.50 per half how with print- 
outs atjust lOp per copy.. The 
main trouble is that rtcrone in 
the library has the remotest 
ideaofhow to use the World 
Wide Web and can't give a 
nnutee any help whatsoever. 
It astonishes me that you 
have to have all sorts of de- 
grees to become a librarian, 
yet when ft comes to learning 
about what will be the future 
of information (fathering and 
research, none of them seem to 
want to know! 
12 



GOT A PC? 

Hem's a way that you might 
be able to help other readers. 
We have to face up to the fact 
that a lot of our readers will 
eventually go over to using a 
PC, even if they intend to 
keep their Atari systems. Spe- 
cifications of PCs change 
almost weekly so it is uirtuaJ- 
ly impossible to recommend a 
particular set- up as being the 
best far a particular purpose. 
If you already have a PC, 
how about writing to us to let 
us know what it ts. Who 
makes it? What processor do 
you have? What 'extras' are 
installed? Has If been reli- 
able? How often does it break 
down? Does the manufacturer 
give good service? Does it do 
all you wanted it to do? 
Wotild you now go for some- 
thing different? 
Tell us about your experi- 
ences for the next Mailbag, or 
for a special article, and your 
experience and advice could 
help others in their decisions. 
Reading reviews in PC maga- 
zines is pretty useless, as all 
they want to do is push the 
iatest supersystem and they 
make it sound as if" you may 
as well not bother unless you 
have the latest 45QMhz pnr 
cessor with a DVD drive, and 
to them £1,000 ispeanutsl 
Page 6's New Atari User 



THE 

ACCESSORY SHOP 

is 
still going! 

Check your PD catalog 
and try to order a few 
disks mis issue - it will 
really help us with our 
last six issues 



Your practical experience is 
far more ualuable to readers 
U»ho want to make the com- 
mitment so share it with us 



And „ believe it or notfolks, 
that was it far Mailbag this 
issue even though them has 
been a long gap between 
issues. When I first started 
this issue a couple of months 
ago we only had £loo letters/ 
Let's haue a lot more for the 
next one, there is still plenty 
to talk about The address, as 
altuays, is: 

MAILBAG 

NEW ATARI USER 

P.O. BOX 54 

STAFFORD 

ST16 1DR 



MtL/M 




PROGRAMMING 



SUPERCIRCLES 



Joel Goodwin does 
the maths to help 
you to draw the 
perfect circle - 
well, almost! 



Drawing a circle Is something that fs 
necessary from time to time but the 
standard routine ts slow. This article 
describes an attempt to speed up thfc routine 
by using an alternative approach. 



THE IDEA 

The usual way of drawing a circle Is to use 
Pythagoras" theorem. You can use a SIN /COS 
function approach, but this turns out to be 
slower, Pythagoras' theorem relates the 
radius to the X and Y coordinates of a point 
on the circle, so by varying either the X or Y 
coordinate we can determine the other. 
However, the formula used is Y=SQR(R*R- 
X*X) which Involves a square root function; 
this is what drags the subroutine down. We 
can optimise the method by using the circle's 
symmetry to reduce the amount of work wc 



need to do, but SQR Is slow and Ideally we 
would like to replace it with something more 
efficient. 

The SQR-routliie treats the circle as a collec- 
tion of points and each point Is found Indi- 
vidually. Another approach is to try to follow 
the path of the circle; that is, each new point 
is thought of as an "update" of the previous 
point This is possible through an approxima- 
tion of the slope of the circle; It Involves a 
lltde calculus, so If you're Interested see the 
Mathematics section at the end of this article. 
This new approach replaces the SQR function 
by an addition and can also be accelerated by 
relying on the symmetry of the circle. The 
resulting "Superclrcle" subroutine is demons- 
trated In Listing 1 . 



THE DEMONSTRATION 

The demonstration program will first com- 
pare the speed of the standard and supercir- 
cle routines. After this. It will then attempt to 
erase standard circles with supercirclcs. This 
will show you that the supercirdes are not 
the same as the standard circles; personally, 1 
prefer the superclrcles but it Is up to you to 
decide which one you like best The program 
will then show you a filled supercircle and 
finally proceed to draw two large circles In 
graphics mode © (one is a standard circle, the 
other is a supercircle), 
The difference in speed will not be so signl- 



Page 6's New Atari User 



13 



SUFERCIRCLE5 DEMQ 
Joel Goodwin 



NP 2 REM ~ 
XD 3 REM = 

PK A REM =1_ 

jp 5 rem = \m atari user - \m = 

NT 6 REM —— " = ==z--.:^-..„ „^ = 
X3 20 GRAPHICS 7: PIKE 711, 4: POKE 7BB,IB4; 

POKE 7ft? ( 24:P0KE 752,I:DIN Ht(48> 
EH 39 M*= B First we draw 2 nnrnal circles, 

a :GDSUB 4989 
FX 48 COLOR 1:XC=2&;tT>2I:R=1?!GOSUB 1988 
AK 59 XDH3?;YC=59:G0SUB 1899 
MF 6$ Ht= l Na* cortpare with 2 supercircles 

.■sGOSUB 4BPB 
CA 78 COLOR 2:XC=13?rYC=28:GQSlJB 2380 
SN 89Xt>28tYC=5?:G0SUB 2BH 
1*1 98 HS=* Natch super circles erase normal 

ones,':G0SUB 4989 
XG 188 XC=79:YC=39 
DB 118 FOR R=3? TO 1 STEP -5 
DY 128 COLOR hGOSUB {888 
El 139 COLOR 8:GOSUB 2800 
JL 148 NEXT R 
CP 158 m='Me can also -fill a Urge super 

circle.' :G0SUB 4998 
OU 168 XC=7?:YC=39:C0L0R 2:R=39:GOSUB 388 

& 
Tl 178 Mt^'Finally two huge node 8 circle 

s.'iGOSUB 4888 
CD 188 GRAPHICS 24:P0KE 789/l2:POKE 718,8 
PD 198 COLOR l:XC=P5;YC=95:R=95!GQSUB 188 

9 
m 288 XC=?24;G0SUB 2888 
ME 218 GOTO 218 

TN 999 REM NORMAL CIRCLE ROUTINE 
FX 1888 FOR DX=9 TD R/SflR<2) 
FA J IIS DY=SQiKRaR-DXSDX> 
MQ 1828 PLOT XC+OX,YC+DY;PL0fT XC-DX,YC*DY 
YC \m REM DX=INT(R)ESIN(THETA)>;DY=1NT(R 



5CDS(THETA)) 
02 1838 PLOT XC+DX ,YC-DfY: PLOT XC'DX P YC-DY 
MK 1948 PLOT XC+DYjYC+QXiPLOT Xt-DY t YC+DX 
QT 1859 PLOT XC+DVC-DXiPLOT XC-DY f YC-DX 
W tm NEXT DX RETURN 
XS [999 REM SUPERCIRCLE ROUTINE 
GH 2888 DX-9:DY=fi 

MO 2910 PLOT XC+DX^C+DYiPLOT XC-DX,YDDY 
OX 2928 PLOT XC*DX,YC-DY:PLOT XC-DX,YC-DY 
MI 2A38 PLOT XC+DY,YC+DX!PLSU XC-DY,YC*DX 
QR 2848 PLOT XC+DYpYC-OXiPLOT XC-DY.YC-DX 
HA 2858 DY=E>Y-{OX'DY):DX=DX+l 
ID 2855 REM DX=DX+l!DY=DY-CDX/DY) 
XG 28i8 IF UX<=DY*I THEN 2818 
AV 2878 RETURN 

JU 2999 REM FILLED SUPERCIRCLE ROUTINE 
GI 3899 DX=9:DY=R 
M2 3118 PLOT XC+DX,YC+DY:DRAWTQ XC-DXjYC+ 

DY 
AM 3929 PLOT XC*DX,YC-DY:DIWMTO XC-DXjYC- 

OY 
VT 3939 PLOT XC*DY,YC+DX:DRAHTO XC-DT.YC* 

DX 
AG 3949 PLOT XC+DYJC-DX iDRAWTO XC-DY.YC- 

DX 
HB 3858 DY=DY-<UX/DY):DX=DXH 
YE 38 A8 IF DX(=DY+I THEN 3818 
AH 3078 RETURN 

]H 3999 REM PROMPT USER FOR KEYPRESS 
TJ mi ? CHR*U25>:PGKE A57,28-LEH(m>/2 

:P0KE dStSjI:? m 
OK 4918 ? " Press any fcev to continue 

SA 4828 POKE 744,255 
"JR 4838 IF PEEK(7<S4I=255 THEM 4838 
SJ 4849 } *[ESC ( DELETE LINE3* | :PCW<E 7*4^2 
55: RETURN 



Undoline = INVERSE CHARACTERS ■ [] - CONTROL + CHARACTER - < > s INVERSE CONTROL + CHARACTER 



14 



Page 6's New Atari User 



flcant If the program la run under Turbo 
Basic, but it Is still noticeable. Turbo Basic 
has its own CIRCLE command, which fs very 
fast (It la written in ML, after ail] and pro- 
duces a circle which looks different to the 
subroutines presented here. 

The program contains three subroutines 
you may find of interest; 

1O00 - D«W standard circle 
2000 - Draw super circle 
3000 - Draw filled super circle 

Each requires XC and YC to be the coordin- 
ates of the centre of the circle and R to be the 
radius, but they do not alter these variables. 
You shouid also use a COIjOR command to 
select the colour of the circle prior to the 
"GOSUB <circle subroutino". (Remember 
that placing a routine at the start of a prog- 
ram may improve its speed,] 

The supercede routine can generate a diffe- 
rent circle by swapping the order of the up- 
dates to the X and Y coordinates: the com- 
mands after the REM on line 2055 can be 
used to replace those on line 2050 if you wish 
to sec the effect, Note that deleting 2055 
altogether will make the subroutine a little 
more efficient, as the line is superfluous to 
the routine. 



THE BUG? 

You may notice that the large mode 8 stan- 
dard circle seems to suffer from a little wiggle 
at the top and left edges of the screen. This is 
not a bug in the method but actually in Baste 
itself. 

Listing 2 is a program which isolates the 
bug. What this program docs is to plot the 
points corresponding to the following sequ- 
ence of coordinates: 



(0,0.5) 


(0.10.5) 


(1 ,0.05) 


(1,10.05) 


(2,0.005) 


(2,10.005) 


(3,0.0005) 


(3,10.0005) 



You would expect all of the points to form 
two straight fines except for the first pair of 
points which should be Just below the fine 
(Basic should round up 0.5 to 1 and 10.5 to 
11). This prediction Is correct for the second 
line, but the first wobbles up and down) 

1 have no explanation for this phenomenon, 
but it doesn't happen If you replace 0.5 with a 
smaller number like 0. 1 , 0.4 or even 0.4999. 
The wobble is clearly connected with Basic's 
roundlng-up mechanism - this bug is NOT 
present in Turbo Basic. The fact that the 
superclrele subroutine does not exhibit this 
problem demonstrates farther how robust the 
new method Is. 



THE END 



I have not seen this subroutine developed 
elsewhere, so I am assuming it Is new. The 
siipcrcirclc method could be applied without 
too much difficulty in machine language, 
although floating point numbers would be 



continued 


on peg* 46 


SY 16 REM SUPERCIRCLES BASIC BUG? 


Ifl li REM Joel Goodwin 


MD 28 GRAPHICS 3:CDLDR 1 




HO 38 Y=6,5 




RC 48 FOR X=B TD 39 




CE 56 PLOT X,Y:PL0T X.Y+II 




UU rt Y=Y/18 




OA 7ft NEXT X 





Page 6's New Atari User 



15 



PROGRAMMING 





by John Foskett 



When organising sporting events 
where many teams compete against 
each other, some form of correlating 
the individual scores and displaying the over- 
all results in a clear and concise way Is re- 
quired. The organisation of our national game 
over many years has lead to the football 
league tables as we know them today and 
"League Table" wag written lO reflect the same 
principles exactly. In the same way as the 
Nationwide football league and the Carltng 
Premiership, League Table gives 3 points for a 
win, 1 point for a draw and no points at all for 
a loss. League Table allows you to create new 
blank league tables, to update them by enter- 
ing the Individual scores and to display the 
tables on screen together with the option to 
print the tables out using an Epson compati- 
ble printer. League Table also sorts the com- 
peting teams into order in accordance with 
the points accumulated and where teams are 
on equal points, using the goal difference in 
the same way as the football league tables. 



THE MENU 

Upon running the program, the following 
menu is presented and each option on the 



menu Is described below. 



{A) LOAD DATA FROM DISK 

{&) SAVE DATA TO DISK 

(C) SORT DATA 

(D) CREATE LEAGUE TABLE 

(E) DISPLAY LEAGUE TABLE 
(f) ENTER RESULTS (UPDATE) 
(G) LIST FILE DIRECTORY 

(A) LOAD DATA FROM DISK: Upon selecting 
this option, a number from to 9 Is prompted 
for to access one of the ten data flies pre- 
viously saved to the disk. If the selected file in 
not on the disk, then an error will result and 
ESCAPE must be pressed to exit. ESCAPE 
may also be pressed to exit from the prompt 
without loading data and without corrupting 
the data currently in memory. 

(&) SAVE DATA TO DISK: When this option is 
selected, a number from to 9 is prompted 
for in the same way as option 'A above in 
order to access one of the ten data files. 
Selecting the number of a previously saved 
file will cause that file to be overwritten with 
the current data. If the selected file has pre- 
viously been locked (using DOS), then an 
error will result requiring ESCAPE to be 
pressed to exit. ESCAPE may also be pressed 
from the prompt to exit without the current 
data being saved, 

(C) SORT DATA: Immediately this option is 
selected, the current data in memory is sorted 
into order according to the number of points 



16 



Page 6's New Atari User 



the teams have accumulated and If some 
teams are on the same number of points, 
then the goal differences are taken into 
account The goal difference being the differ- 
ence between the total number of goals a 
team has scored in the league and the total 
number of goals scored against them- This 
option can only be selected with data In mem- 
ory, but If selected with no data in memory, 
then ESCAPE must be pressed to exit. 

(D) CREATE LEAGUE TABLE:Tkls option Is 
used to create a new blank league table, If 
this option is selected with data currently In 
memory, then the option to continue Is given 
by pressing either T for Yes or 'N' for No, If TT 
is pressed to continue, then any data current- 
ly in memory Is erased, but if N h for No Is 
pressed, then any data currently in memory 
Is preserved, A league may consist of up to a 
maximum of 24 teams or a minimum of 1 
teams. The team names may consist of up to 
a maximum of 16 characters each in any 
combination of uppercase letters and spaces. 
Exit is automatic after entering the 24th team 
name, but TAB must be pressed to exit with 
less than 24 teams, but note that a minimum 
of 10 team names must be entered before TAB 
is enabled. After exiting in both cases. 
ESCAPE must be pressed to exit back to the 
menu. At this point the new blank league 
table data Is contained in memory and so it is 
only a matter of saving it to disk using option 
'B' as previously described. Note that pressing 
ESCAPE to exit at any other time will erase 



the newly created data from memory and also 
note that any team name entered which is a 
repeat of a previously entered team name 
cither in full or in part will be rejected. 

(El DfSPLA Y LEAGUE TABLE; This option is 
used to display the data currently in memory 
on screen in the form of a league table, but 
note that for a true representation, the data 
in memory must first be sorted Into order 
using option 'C as previously stated. If this 
option is selected without any data in mem- 
ory, then ESCAPE must be pressed to exit- 
League tables are displayed on screen In the 
same way as the football league tables are 
shown on television, with the team names in 
a column on the left followed by columns of 
figures on the right hand side. Following the 
team names arc the number of games the 
teams have played, the number of points the 
teams have accumulated, the number of goals 
the teams have scored, the number of goafs 
the teams have had scored against them and 
their overall goal difference. The league tables 
are displayed In four colour zones for clarity 
Indicating the top or championship position 
in brown, the next three promotional posi- 
tions In green, the relegation positions In red 
and the bulk of the table, the middle positions 
In the normal Atari blue. No matter how many 
teams are In the league, the bottom three 
positions will always be shown in red because 
the relegation zone Is moved accoidlngly and 
if necessary the remaining part of the screen 
below the relegation zone will be blanked out 
with the background colour. ESCAPE is 
pressed to exit back to the menu or P k is 
pressed to printout the league table using an 
Epson compatible printer. Because of the 
extra width available when using a printer, 80 
columns as opposed to 40 columns on screen, 
extra data has been Included in the printout. 
When printed out, the league tables include 
the teams full home and away records, re- 
cording the total number of wins, draws and 
defeats for both home and away matches. 



Page &$ New Atari User 



17 



- 






(F) ENTER RESULTS (UPDA TE}: This option is 
used to update a league table by entering the 
relevant results, but if this option Is selected 
with no data In memory, then ESCAPE must 
be pressed to exit. All the team names In the 
league arc displayed on screen In their correct 
league positions for reference, assuming of 
course that the data has previously been sor- 
ted into order using option h C as previously 
described. Entering the result (or the score) of 
a match is achieved by first entering the 
name of the 'home' team followed by the name 
of the 'away" team after which the result of the 
match is entered. The result is entered by 
pressing a numeral key (0 to 9), entering the 
home teams score first followed by the away 
teams score. When entering the team names, 
the names may be abbreviated to the first few 
letters if required, but be careful to match 
with the correct team, the full name still being 
printed on screen even If abbreviations are 
used. Normally only the first three or four 
letters need be entered, but it depends upon 
the names of the teams in the league and 
upon their league positions. To distinguish 
between Manchester Utd. and Manchester 
City will obviously require at least the first 12 
letters to be entered. After entering the team 
names and the result, a prompt Is given 
asking if the en tencd result is correct and if so 
T 1 for Yes is pressed to enter the result or 'N' 
for No is pressed If the entry is In error. Upon 
pressing "Y\ the current data in memory Is 
updated and the two teams are marked c-n 
screen accordingly with an inverse 'H 1, or an 
inverse 'A' to signify home or away for refer- 
ence to show that the results for the marked 
teams have been entered. Note that these 
marks are erased when exiting and are not 
replaced should this option be reselected. If 
when prompted, 'N' was pressed, then the two 
team names and the result are cleared and 
the current data in memory is not updated. 
Entering the results continues in this way 
until ESCAPE is pressed to exit but note that 
option 'C must be used to sort the data into 
oidcr before a true league table can be dis- 



played or printed out by using option 'E' as 
previously described. 

(G) LIST FILE DIRECTORS This option Is used 
to list all the league table data files on the 
disk for reference. The program allows for up 
to ten files to be stored on disk and this 
option lists each one found as a single num- 
eral each separated by commas after which 
ESCAPE must be pressed to exit. 



USING 
THE PROGRAM 

To clarify how to use the program, the first 
process before anything else can be achieved 
is to create a new blank league table using 
option 'D' and then save it to disk using 
option h B\ Initially file is best used to store a 
blank file. Load the blank file using option "A*. 
then use option 'P to update it, use option "C 
to sort the data into order and then use op- 
tion 'B" to save it back to disk, use option E' 
to display the league table on screen and if 
necessary to print out the league table. 

Unlike most programs, League Table has no 
limits to the values that the data can accom- 
modate and so theoretically the program can 
accept the normal six-byte values. Of course 
such large values will disrupt the screen dis- 
play and the layout of the printout but it does 
have the advantage of keeping the league 
table data accurate. 11 all the results of a 
particular football league such as the Carling 
Premiership are entered into the program, 
then at the end of the season as well as 
during the season, the program will produce 
an accurate representation of the actual 
league table. The only discrepancy may be 
when two or more teams have the same num- 
ber of points and the same goal difference, 
but as the season progresses, this becomes a 
very rare occurrence. 



18 



Page 6's New Atari User 



TECHNICAL DETAILS 

ALTERING THE SIZE OF THE 

PROMOTION AND RELEGATION ZONES 

The size of the programs promotion and re- 
legation colour zones on screen arc fixed, but 
they could be altered if required, The size of 
the promotional green zone is established 
directly by calling up the relevant DLI routine 
within the display list at the 52nd clement of 
U$ on line 1860 which Is an Inverse CON- 
TROL-B character. 

To increase the size of the promotion zone by 
one position, move the character one position 
down the string to the 53rd position and re- 
place the original 52nd character position 
With a normal CONTROL-B character. Alter- 
natively to reduce the size of the promotion 
zone. Move the character up the string. 

The size of the relegation red zone Is estab- 
lished by a local POKE into the display list in 
page six within the DISPLAY procedure, The 
local POKE is referenced from the variable 
NUM which is used to store the number of 
teams in a particular league so that the re- 
legation zone always covers the last three 
positions no matter how many teams arc 
actually in the league. "POKE 
1580+NUM. 130'' found on line 690 Is used 
determine the size of the relegation zone and 
the corresponding "POKE 1580+NUM,%2" to 
cancel the DLI call can be found on line 750. 
Note that both must POKE the same address. 
Using "1579 +NUM" will increase the size of 
the relegation zone whilst "lSSl+NUM" re- 
duce the size, 

If the size of the promotion and relegation 
zones are altered, then the position of the 
message "PRINTING TABLE PLEASE WATT" 
displayed when downloading the data to a 
printer will have to be considered accordingly. 
The relevant three lines of the league table arc 
temporarily MOVEd into U$ before they are 
overprinted on screen with the message after 
which they SM MOVEd back into the screen 



RAM overwriting the message to restore the 
league table. 

THE THREE DISPLAY LISTS 

The first of the three display lists Is used for 
the program's menu and employs mixed text 
modes. One line of mode two and three lines 
of mode one arc used for displaying the prog- 
rams titles and eight lines of mode zero for 
the menu. 

The second of the display lists Is used for 
displaying the league tables on screen and Is 
a normal mode zero display list with three 
extra lines added at the top of the screen, one 
line of mode one for the programs title and 
two lines of mode zero for the league tables 
heading and its two option menu. This dis- 
play list is located at the page six address of 
1573, There are two asterisks at the top of the 
display list where the address of XS {the extra 
lines screen RAM) is DPOKEd. X$ Is defined 
online 1890, 

The third display list defined on line 1870 Is 
a normal mode zero display list but lined and 
with an extra mode one line at the top of the 
screen for displaying the programs title. This 
display list Is used for option "D" to create new 
blank league tables and option n F lo enter the 
results. This display list Is located at the page 
six address of 16 1 1 and it also contains two 
asterisks where the address of X$ is DPOKEd, 
but only the first 20 bytes of X$ are displayed 
since this display list only contains a single 
extra mode one line. 

THE FIVE DU$ AND THE ZONE COLOURS 

The program uses five DLI routines solely to 
provide the colours for the four colour zones 
used when displaying the league tables. The 
five DLI routines are defined together as US 
on line 1 900 and MOVEd Into page six follow- 
ing the display lists at address 1670. 

The DLI routines are loaded with the re- 
levant colour values using the unused loca- 
tions 590 to 594 via the DATA statements at 
the end of the listing on line 1940. Since there 



Page 6's New Atari User 



IS 



are only four colour zones In the league 
tables, only four DATA statements have been 
Included on line 1940 which makes changing 
the DATA easier when altering the colours. 
The fifth colour value of 146, the background 
colour is POKEd directly into location 594 
which Is used to blank out the unused area of 
the screen below the relegation zone when a 
league contains less than the maximum of 24 
teams. 

THE VBI ROUTINE 

A small immediate VBI routine is used to 
disable the attract mode, the CONTROL- 1 
stop- start toggle and to disable the lowercase 
and inverse characters ensuring that the 
keyboard is always in the uppercase mode. 
The VBI routine also resets the DU vector 
register 5 12 to point to the first DLI routine to 
synchronise the screen colours with their re- 
spective zones when displaying league tables. 
The last DLI routine also resets the DLI vector 
register 5 12 as a back-up should the VBI 
routine be suspended during data transfer 
when downloading data to the printer. A de- 
ferred VBI routine is often suspended during 
data transfer so an immediate VBI routine 
has been employed instead. All this results In 
a much reduced screen flicker when printing 
out a league table. The VBI routine is defined 
as VBI$ on line 1870. 

USING A DIFFERENT PRINTER 

The program was written for use with an 
Epson compatible printer but it may be mod- 
ified to use any printer. The printer control 
codes may need to be altered accordingly and 
are to be found on lines 820 and 840. 

For reference when changing the central 
codes, the league table should print out using 
normal size characters with the exception of 
the heading "LEAGUE TABLE" which should 
print using double width, single height char- 
acters in the centre of an A4 sheet at the top 
of the page. The only other deviation is that 
the league tables category heading between 
20 



the words POS' and D1FF' (inclusive) should 
be underlined. 

A STRANGE ENDPROC 

An ENDPROC with nowhere to got At the end 
line 920 of the program listing, there is a 
strangely placed ENDPROC which can never 
be acted upon because it follows a GOTO 
(GO# NODATA)* This ENDPROC is simply 
being used to reset Turbo BASICs indentation 
since there is no direct exit via an ENDPROC 
within the RESULTS procedure which can 
only exit via a POP command back to the 
menu from within the EtTTER procedure* The 
ENDPROC is not an essential part of the list- 
ing but without it, Turbo's indentation is 2 
places indented for the rest of the listing 
which gives the Incorrect impression that 
something is wrong within the listing which 
Turbos indentation is supposed to identify. 



PROGRAM BREAKDOWN 



PROCEDURES 



BEEP 

CLEAR 

CONTINUE 



CREATE 
DISPLAY 

ENTEH 
FILES 

IN IT 
KEY 

LOAD 
MARK 

RESULTS 

SAVE 
SORT 



Generates the beep 

Clears the menu marker 
Used with the CREATE procedure 
requiring "Y ! or W to be pressed to 
continue 

Creates new blank league tables 
Displays the league tables on screen 
and downloads the data to a printer 
Controls the entering of team names 
Reads the disk's directory and dis- 
plays all data files found on screen 
Initialising routine 

Gets a key press from the keyboard 
Loads a data file from disk 
Marks the menu options when selec- 
ted in inverse 

For entering the individual results of 
the matches played 
Saves a data file to disk 
Sorts the data in memory into order 



Page 6's New Atari User 



SWAP Used within the SORT procedure to 

swap over adjacent team names and 
Ihe respective data if the lower team 
has a greater number of points or 
when teams are on the same num- 
ber of points, the better goat differ 
ence 

LINE LABELS 

MENU Start of the menu 

NODATA Start of the NO DATA routine 
SELECT Start of the 'select from menu' 
Routine 

STRINGS 

B$ Defined with 15 spaces following an inverse 

space to erase team names when necessary 

and providing a new cursor 
F$ Defined as LEAGUE.DT* {meaning league 

data) where '*' is Ihe numeral selected when 

saving files to disk 
IS Used m the ENTER procedure to store me 

data as a team's name is being entered 
LDS Line (down). 40 Cntri-M characters 
LUS Line (up). 40 Gntrf-N characters 
NS Dimensioned to 16 characters and normally 

used to identify team names from Tf 
PS Used when printing out league tables 
T$ Simulated string array for storing all the team 

names in a league 
U$ General purpose string 
X$ The screen RAM used for the extra screen 

lines 
Z$ Defined with zero characters (the heart) used 

for erasing text from the screen 

THE ARRAY 

A(V,H): Where V (vertical) represents the num- 
ber of teams in ihe league minus one, that is on a 
scale ol to 23 and where H' (horizontal) repre- 
sents Ihe following league table data.... 

H=0 Games played 

H=1 Points accumulated 

H=2 Goals scored 

H=3 Goals scored against 



H=4 


Home wins 


H-5 


Home draws 


H-6 


Home defeats 


H=7 


Away wins 


H-e 


Away draws 


H-e 


Away defeats 


VARIABLES 


AW 


Identifies the away team 


AWAY 


The away team's scare 


HM 


Identifies the home team 


HOME 


The home team's score 


H,|,J.K,L General purpose variables 


NUM 


Stores the number of teams in the cur 




rent league 


OPT 


The menu option 


SCR 


The address of the screen RAM 




DPEEK{88) 


Z 


The address of 2$ used when erasing 




text from the screen 



Many of the program's constants have been con- 
verted into variables to conserve memory. The 
values of these constant variables never change 
and are easily seen since they are preceded with 
the letter N' thus N4=4. N8=8, N 10=10, 
IM 100=1 GO. etc. 



AND FINALLY ... 

Please don't get the impression that i am interes- 
ted in football after writing this program! My only 
interest in football is that I am a Womble, bom and 
brought up in Wimbledon, a stones throw from 
Plough Lane, the original home of Wimbledon FC 
and my wife was bom and brought up in Brent- 
ford, her father an ex- Brentford player. 



THE LISTING 

The/uJl listing can be found an this issue's 
disk. If yau prefer to type in the listing a 
TYPO coded, printed listing is available on 
request see inside back cover for details. 



Page 6's New Atari User 



21 



PROGRAMMING 



AUTOMATIC 

PROGRAMMING 



H S Wood 
demonstrates the 
unique Atari 
Return Key Mode 



The ATARI 8 bit is capable of writing 
it's OWn lines for a program and this 
technique can be very useful. 
I have included a simple example program 
called RTRNDEM.BAS which has full REM's 
to indicate how the lines perform the 'magic - . 



METHOD 



Basically one clears the screen, makes a 
program line a few lines down the screen and 
prints the word 'CONT on the following line. 
The cursor is then moved above the line, and 
value 13 is poked into location 842. The 
'STOP command causes the program to stop 
and the cursor then moves down the screen 
to the printed line which is entered into mem- 
ory. The cursor continues to the 'CONT line 
and the computer re-starts* Next the value 12 
has to be put into location 842 and the prog- 
ram is again running normally. The END 



command ends the run. 
The value 13 In 842 means H Read from the 
screen instead of the keyboard' so that, any- 
thing on the screen Is input to the computer. 
This 13 mentioned In 'Mapping the Atari 1 and 
In 'Sams Programmers Reference Guide' both 
of which are probably unobtainable but may 
be In lending Libraries for reference. 



PROGRAMS 

Tf the program Is made to 'LOOP' many lines 
can be produced and a good example of this is 
a routine called MCDATA.BAS which pro- 
duces 'DATA' lines from a machine code prog- 
ram in memory. The example I have provided 
for making 'DATA' lines Is a modified version 
of a 5 line program published in ATARI USER 
dated November 1986 and written by Jeff 
Davis. 

My modifications are to make it easier to 
lype the program (there is a lot of program for 
5 lines) and also to allow memory addresses 
to be entered in either 'I J EX' or DECIMAL', 
HEX is usually easier to use when dealing 
with machine code. 

To use MCDATA.BAS type RUN" and follow 
the prompts. The DATA lines made by the 
above program should be L LISTcd to disk so 
that the program itself js not Included. Also 
MCDATA.BAS should be protected so that it 
docs not get corrupted. 



22 



Page 6's New Atari User 



DRAWING GRAPHS 

A different program might draw graphs and 
thus use a FORMULA. This formula can be on 
a single line and will be used every time the 
program is run. However if the formula Is to 
be changed to draw a different graph the 
RETURN KEY MODE can be used to write the 
same line with a different formula. 

I have a GRAPH drawing program which 1 
call FUNCTN.BAS which is included on this 
Issue's disk. Check the program out to see 
how it works. When asked for "X' values type 
-10 and 10. The formula already in the prog- 
ram Is Y(I)=SINIX). 

Similarly a program might READ' from a file 
and If the FILENAME has to be typed each 
time ihe program is "RUN' it becomes tedious. 
Instead a message can be printed to ask 'Do 
you want to change the Filename". Typing 'N' 
will run again with the same filename while 
'V will ask for the new filename and the prog- 
ram will write a line with the new filename. 
This filename will continue to be used until Y 1 
Is typed again. 



OTHER USES FOR 
THIS TECHNIQUE 

Other uses for this technique include delet- 
ing lines of a program after it has 'LQAD'ed. A 
long program which 'LOAD'S a lot of machine 
code from DATA' lines can have the DATA 
lines deleted after they have served their pur- 
pose thus taking up less room In memory. 
There are many more possibilities and Atari 
users will be able to think of plenty. • 

The MCDATA.BAS program can be found on 
the Issue disk. 



ei j rem X3xs3ixxsixx333mxxx*xxx*xxx** 

B 2 REM * RETURN KEY MODE 0£H0 X 

HJ 3 REM X FOR NEW ATRI USER X 

W 4 REM X By H S WOOD X 

FU 5 REM * APRIL 1998 3 

en 6 rem mmmmummmmmn 

m 7 REM 

HC 18 REM m SET LINE fe.=H8B III 

HQ 15 LlNE=im 

EE 45 REM III CLEAR SCREEN 333 

ZG 59 1 ■[ ESC, CLEAR]' 

NE 65 REM XX PRINT LINE No. Etc IN 33 

EB 78 REM XX CORRECT PLACE M SCREEN XX 

IP 75 POSITION 2,3:? LINES" MTA 'j 

EL » REM XIX PRINT ITEMS SEPARATED Xil 

CF 95 REM XX3 BY COhtte's XXX 

NC 188 FDR 1=8 TO 5 

UL 11B ? I; 

DC 115 REM XX COMMA TD SEPARATE ITEMS XX 

OH 121 ? Yi 

FX 138 NEXT I 

Y5 135 REM XX NO COMMA AFTER LAST I TIM XX 

DN 148 ? I 

AH 2BB *EH XXX NW THE 'NflEIC' 331 

TL 215 REM XH PRINT 'C0NT ON LINE XXX 

UY 2 It REM 3XX AFTER DATA LINE XXX 

SC 228 ? 'CONT' 

JC 225 REM X3X MM CURSOR TO TOP 331 

JK 238 REM XXX DF SCREEN XXX 

HT 235 POSITION 2,1 

EH 248 REM XXX SET RETURN KEY' MODE XXI 

m 245 POKE 042,13 

OR 258 REM XXX STOP THE PRO&RflH XXX 

m 255 STOP 

HL 2AB REM XX3 RESTORE 'NQRWL HOPE' XXX 

NC265 POKE 843,12 

DE 278 REM XXX CLEAR THE SCREEN XXX 

BH 275 ? CKW(125) 

HL 288 REM XX3 LIST NEH LINE AND END XXI 

SU 285 LIST IBIB:END 



Untertine s INVERSE CHARACTERS ■ [ ] = CONTROL + 

CHARACTER •< > : INVERSE CONTROL* CHARACTER 



Page G's New Atari User 



23 



Features 

and 



A SHORT HISTORY OF COMPUTERS 



A FVTURA Update 
by Austin Hillman 



The electronic stoned program compu- 
ter Is fifty years old this year. As you 
may know, the prototype of all mod' 
em computers L Baby' has been reconstructed 
In time for its anniversary on 2 1st June 1998. 
But what came before It and what came 
after? 



EARLY 
CALCULATORS 

The first calculating machine Is sold to have 
been built by Wilhelm Schickard around 
1623, but it was later destroyed in a fire. 
Luckily, he described its workings in corres- 
pondence with Johannes Kepler, thus enabl- 
ing a reconstruction to be made of his Calcu- 
lating Clock. This consisted of a version of 
Napier's Bones, for multiplication, sitting on 
top of the mechanical device which carried 
out addition and subtraction. 

Blaise Pascal created The Pascaline' mecha- 



W 



ilhelm Schickard's first calculating machine 
I The Pascaline 



rtical calculator in 1642, to aid his father who 
was a tax col Ice Lor. It was a shoe box sized 
device that could add. subtract, divide and 
multiply, but it was mechanically unreliable 
so only a dozen Or so were made, some of 
which still exist. 
In the lG7G'si Gottfried von Leibnitz created a 
major improvement to the mechanism of cal- 
culators with the invention of the Leibnitz 
Wheel which speeded multiplication. Sadly, 
his own calculator, the Stepped Reckoner, 
was apparently never perfected, as the only 
surviving version is inoperative. 



COMMERCIAL 
PRODUCTION 



The first commercially produced calculator 
using the Leibnitz Wheel, The Arithmometer, 
was created by Charles Xavler Thomas De 
Golmar for use In his insurance company. It 
appeared in 1820, and around 1500 examples 
were sold over the next thirty years or so 
thank to the new demands of the industrial 
revolution. 

The most famous name in mechanical calcu- 
lator design is of course Charles Babbage. He 
designed his Difference Engine in 1 82 1 , in 
order to compile logarithm tables. Unfortun- 
ately Its complexily defeated the engineering 

Leibnitz Wheel 
I 



of the day and it was abandoned in 1842, 

However in Sweden, Edvard Scheutz man- 
aged to build a working Difference Engine in 
1 843, based on the work of his father, Pchr. 
He built another In 1 854 but found little de- 
mand for this remarkable device. 

Undeterred. Babbage next designed the Ana- 
lytical Engine In association with Augusta 
Ada, Lady Lovelace. This was to be the worlds 
first programmable calculator. The machine 
had an input where numbers were entered on 
punch cards, an idea borrowed from the Jac- 
quard loom. The store held the numbers as 
required. The mill performed the arithmetic. 
The output printed the answer. The control 
unit was programmable for the type of calcu- 
lation by punch card. Many different designs 
were drawn up over the years but the 
machine Itself was never built. 

In 1SS5, Dorr E. Felt developed a calculator 
that was operated only by the action of press- 
ing the keys. It was called the Comptometer, 
and was advertised as "the machine-gun of 
the office" in order to emphasise the speed of 
operation. 

In 1892, Williams. Burroughs patented his 
Adding and Listing Machine which also used 
a keyboard. It was not key driven, but it was 
the first to produce a print out of the results, 
it became a best seller. 

The American census of 1890 was processed 
by a punch card tabulator created by Herman 
Hollerith, who Joined with others to create the 



company which would become International 
Business Machines (IBM) in 191 1. 



ENTER 
ELECTRONICS 

in 1930, Dr. Vannevar Bush of the Mas- 
sachusetts Institute of Technology produced a 
Differential Analyser, based on a paper writ- 
ten by Lord Kelvin in 1876. Copies of this 
device were built at several universities. In- 
cluding a Meccano version built at Manches- 
ter in 1935. It was an electro- mechanical ana- 
log computer designed to solve differential 
equations, but it was still basically just a 
calculator, albeit a powerful one. However 
things weth: about, to change. 

In 1937, the brilliant mathematician Dr. 
Alan Turing published his paper 'On Comput- 
able Numbers with Em Application to the En- 
tscheidungsproblem'. This paper lay out the 
theoretical concept of a machine that we now 
call a computer. All that was needed was 
someone to build a practical device. 

Research mathematician George Stibitz cre- 
ated his Model K (for Kitchen) computer In 
1937, This was a device using relays that 
could add binary numbers. Developing the 
idea at Bell Labs, his Complex Number Calcu- 
lator was completed in 1939. Bell was not 



1623 



1642 



1670 



24 



Page 6's New Atari User 



Page 6"s New Atari User 



25 



very Interested In developing it, but the U,S, 
Army was, they took delivery of five relay 
computers for ballistic computations. This 
range reached its peak with the BTDS of 1949, 
although research continued into the 1950s. 

Meanwhile In Germany, engineering student 
Konrad Zuse began work on a binary compu- 
ter in 1936. to aid his work at Henschel Air- 
rraft. The Z 1 was a mechanical demonstra- 
tion model using switches and bulbs. The Z2, 
completed in 1939, used relays. Military 
funding for a code breaking model was re- 
fused in 1940. Continuing to work almost 
unaided, Zuse and colleague Helmut 
Schreyer, built the 23 in 1941. This used 
2600 relays and was controlled by instruc- 
tions on punch Lapc, The partly electronic Z4 
was completed In 1945. His company, Zuse 
AG, founded In 1949 would form the basis of 
the German computer Industry, becoming 
partofSelmcnsin 1967. 

Back in America, Harvard engineer Howard 
Aiken had designed a relay computer, based 
on the Ideas of Babbage, In 1937. He per- 
suaded IBM to build the Harvard Mark I 
Automatic Sequence Controlled Calculator In 
1939, It was finally completed in 1944. The 
Mark 11 arrived tn 1947. The Mark 111 tn 19S0 
and Mark IV in 1952. These relay computers 
were large, expensive, and only ten times as 
fast as a mechanical calculator, but they were 
reliable and could work 24 hours a day. 



A 30 TON 
COMPUTER! 



During the war America was desperate for 
accurate ballistic tables. Physics Professor 



John Mauchly proposed an electronic compu- 
ter in 1942 but it was not until April 1943 the 
Army sanctioned the building of the Electro- 
nic Numerical Integrator Analyser and Com- 
puter - ENIAC. It finally entered service In 
February 1 946. It was a huge device contain- 
ing 18000 valves and weighing 30 tons. It 
could handle numbers of up to 20 digits and 
hold 10 of these numbers in its store. It was 
also very fast, up to 5000 calculations per 
second. 

Tt had been thought that ENIAC was the first 
electronic programmable computer. However 
the UK government revealed in October 1975 
that an electronic computer, code name Col- 
ossus, was operational at Bletchley Park in 
December 1 943 , and that ten units were 
operational at the end of the war. They re- 
placed relay based machines that had been 
used from 1941, These 1 50 & valve code 
breaking machines were built by Professor 
M.ii.A. Newman and T.H. Flowers, based on 
the ideas of Alan Turing. Development was 
continued on the Colossus design at the 
Radar and Telecommunications Research 
Establishment until 1963. 

Work began on the successor to ENIAC, the 
Electronic Discrete Variable Automatic Calcu- 
lator - EDVAC, In 1946. It was eventually 
completed In 1951, as in the meantime John 
Mauchly and J,P,Eckert had left the project to 
form their own computer company. After 
creating BINAC for Northrop Aircraft in 1948, 
they produced a commercial computer, UNI- 
VAC 1, in 1951, the first to use magnetic tape 
for storage of data. Remington Rand bought 
the company in 1952 and sold 46 units, the 
last of which was turned off In 1970. 

Mathematician John von Neumann had 
worked with Alan Turing in the late 30's. He 
published an Influential paper on the design 

nee Engine Edvand Sdieutz'* 

Different Engine |^ 



Babble's Diff 
The Arithmometer 



fterenc 



of a stored program computer in 1946, After 
working on EDVAC he created the IAS com- 
puter at the Institute of Advanced Studies at 
Princeton in 1952, This machine was to 
heavily influence future computer design. 
At the National Physics [Moratory, Turing 
designed Qie very powerful Automatic Com- 
puting Engine - ACE, before Joining the Man- 
chester University team in 1 948. ACE was 
eventually built In 1957 after the less ambi- 
tious Blot ACE had been constructed. This 
was to form the basis for the English Electric 
range of commercial computers. 



THE FIRST 
REAL COMPUTER 

The first stored program computer was 
therefore the Manchester University Mk 1 

Baby", created by Professor Frederick Wil- 
liams and Doctor Tom Kilbum. This 600 valve 
unit, capable of processing 800 instructions 
per second, used a memory device known as 
a Williams tube. This was basically a cathode 
ray tube adapted to store 128 bytes of infor- 
mation. The Manchester team later collabo- 
rated with others to produce a commercial 
version, the Ferranti Mk 1 in 1951, which 
lead to the Pegasus of 1959, followed by the 
Mercury and then the Atlas, the fastest com- 
puter available In 1963. 

Cambridge University produced EDSAC - 
Electronic Delayed Storage Automatic Calcu- 
lator, a scaled down version of EDVAC, in 
1949, The Cambridge team also assisted with 
die design of the Lyons Electronic Office, a 
massive 6000 valve unit, whose 'memory' was 
a collection of mercury tubes weighing half a 
Analytical Engine 

_L 



ton. This was developed Into the LEO 1 com- 
mercial computer of 1954. Leo Computers 
Limited built about 100 units and became 
part of English Electric in 1964. 

Birkbeck College produced experimental 
models based on the IAS design,, which were 
the inspiration of the commercial units made 
by the British Tabulating Machine Co., now 
known as IntemaUnnal Computers Limited. 

The mighty IBM despite building the Harvard 
computers was not really interested in this 
area uniil it was approached by the US gov- 
ernment It built the IBM 701. based on the 
IAS design, tn 1953. It was surprised to get 18 
orders for this model. Now convinced there 
was a demand for computers, the IBM 702 
and 704 were launched in 1955 for commer- 
cial use. 



FIRST USE OF 
TRANSISTORS 

Transistors, invented in 1947, were first 
used in the TX-O fTransistor experimental 
computer) built at MTT In 1956. They finally 
supplanted the mighty valve In the IBM 7000 
scries of 1 959, 

Integrated circuits, created In 1958, first 
appeared in the IBM System/300 range of 
1 964. The BASIC programming language was 
invented by John Kemeny and Thomas Kurtz 
that year. 

The Intel Corporation, founded in 1968, 
pioneered the development of memory chips. 
And It was here that Marclan E, Hoff produced 
the first microprocessor, the 4004 (a 4 -bit 
processor intended for use in a pocket calcu- 
lator), in 1971. 

Comptometer Adding and Listing Midline 

IBM i 



IBM found cd 



1820 T821 



1343 1850's 



1885 



1892 



1911 



26 



Page 6's New Atari User 



Page 6's New Atari User 



27 



THE HOME COMPUTER 

The first home computer was the the Altair 
8800, launched as a kit In December 1974. 
by Micro Instrumentation and Telemetry Sys- 
tems, It used the Intel 8080 eight-bit microp- 
rocessor {1973) and had a minuscule 256 
bytes of ram to work with. Basically a large 
box with some switches and pretty lights on 
the front it could do very little. It cost $397. 

In 1976 the 6502 microprocessor was Laun- 
ched by MOS Technology [based on the 
Motorola 6800 of 1974) and used in their KIM 
1 (Keyboard Input Monitor 1) kit computer. 
The success of this crude device supposedly 



encouraged Commodore to launch the PET 
(Personal Electronic Transactor) in June 
1977. 

The home computer boom was now just 
around the corner, the Atari 400 and R00 
would soon arrive to do battle with a flood of 
micro's that came and went in the 80' a. Brit- 
ish proved to he best as the Sinclair range 
saw off allcomers, including the Japanese 
with their compatible MSX models. The IBM 
54k PCjr of 1 98 1 initially seemed to be 
another failure but after a slow start the PC 
and Its many clones have emerged as the 
winners of the hardware battle - at least for 
now. ' 



Differential Analyser 
I 



Turing's theoretical paper on computer^ Model K computer 
11 binary compute* 
Colossi!* 
Harvard Mark I Autcavatic Sequence Controlled Calculator 

Etectronk Numerical Integrator Analyser and Computer ■ ENI AC 
ED SAC - Electronic Delayed Storage Automatic Calculator 

Electronic Discrete Variable Automatic Calculator ■ EDVAC/UNfVACl 
I AS computer 
IBM m 
LEOT 

TX'O {Transistor experimental cOmputer) 

Automatic Computing Engine - ACE 
IBM7WK1/Pegasus 

Intel Corporation founded 

First microprocessor 

Atari invents Pong 

Fist home remputer kH - Altair 8800 
65ffi mitraprftcessor launched 
Commodore PET 
Atari MOTH 

Home Compiler Boom 
IBM Mk PCjr 
PC's dominate ihe world 



Alias 

IBM 

Systen 
litt 



I 



1930 



26 



19371939 1943 1946 1949 195215541956 1959 19f3 19*3 1971 1974 1977 ISW* 
1944 1951 19S3 1955 1»7 «H 1972 197619791981 

Page 6's New AUiri User 



1990-?- 



PROGRAMMING 



TEST CARD 



John Foskett helps 
you set up your TV 
for the perfect 
picture 



The test card utility program was writ- 
ten as an aid for television and moni- 
tor alignment to ensure that they give 
the best possible display. This program, a test 
card or any pattern generating equipment is 
used to provide a standard image on screen to 
give a visual indication when selling up the 
Internal adjustments of a television set or a 
monitor. 



CAUTION! 



At this point a cautionary note is necessary, 
television and monitor alignment is a skilled 
job which should NEVER be attempted with- 
out prior knowledge. Such equipment con- 
tains very high voltages which can be danger- 
ous so ALWAYS be careful Remember at all 
times that electricity cannot be seen, heard, 
smelt or tasted, it can only be felt and once 
felt it might be too late, so treat electricity 
with the respect it deserves! 



POOR QUALITY 
PICTURES 

It. is really amazing how so many people put 
up with poor quality pictures when watching 
television, but much of the time they are 
unaware of the problem simply because the 
quality of a picture deteriorates very slowly. It 
is extremely difficult to notice misalignment 
when watching normal television pictures* 
but the problems show up clearly when using 
a test card or a pattern generator 



USING 
THE PROGRAM 

The Test Card program provides a grid of 
ho rizontal and vertical lines which are evenly 
spaced with a large circle in the centre. This 
Is used to ensure a good linear display such 
that the lines are evenly spaced over the en- 
tire screen both horizontally and vertically 
and also that the circle is circular and not 
elliptical in anyway- The lines should appear 
straight without any curvature or kinks- 
Within some of the boxes formed by the grid 
and spread evenly over the screen are small 



Page 6's New Atari User 



29 



m 18 REM HHimiHSHiEHXHmmZ 


TDZljPLGT l+J.ZBsOfMWTG I+J,19l!NEXT 


DK 28 REM i THE TURBO TEST CARD 3 


J:NEXT I 


US 38 REM * FDR MONITOR AUGMENT * 


CI 2 IB FOR 1=15 TO 31? STEP 48; FOR J=23 T 


HR 48 REM I WRITTEN BY JOfW FOSKETT S 


198 STEP 4B:PL0T 1, J: PLOT HX1,J:PLQ 


DO 45 REM * 3 


T I.J+XlsPUTT l+Xl,J+3tl:MEXT J:NEXT I 


KL 58 REM I NEW ATARI USER - 1PPB Sf 


YS 228 FOR 1=159 TO 148: FOR J=?5 TO ?4:CI 


PR 6i REM HH*mmmH*X**H3(HH 


ROLE I,J,95:NEXT J;NEXT I 


BN 65 REM 


LW 238 REM Print Text 


BF 7BN24=24iGHAPHlCSNZ4:PaKE I4 f A4iPDKE 


Iti 241 TEXT 48,XB, , TH£ TURBO* :7EXT 2Bfl,ZB 


53774,44: POKE 7i8^8:N6^3+^3iCOL="^: 


,'TEST CARD'iTEXT i4,lB4, , J0W FOSKETT 


EXEC COLOUR :N254=Hd 


*jTEXT 215,184 P , »RCH 1997' 


MD 88 RESTORE 38§:F0R 1=8 TO 33eREAD J:PO 


RF 258 REM Turn On PMGs 


KE 1534+1, J :ND(T I 


GX 24B POKE 559,58: RESTORE 248: FOR l=7.i T 


BJ n RESTORE ?§eFOR I=K( TG No : READ J:PO 


Z3:READ JsPOKE 53248+I J J:NEXT hOATA 


■KE DPEEK(5iB>+J,i43:NDCT 1:DATA 1B,4fl, 


15,289,184,138 


44,89,114,138,142 


YS 271 REM Options 


PL 188 POKE 54284 ,21 ;DPOKE 512,1 536 :DPOKE 


EA 288 DO :I=PEEK(5327?}:IF 1=H4:C0L=C0L+ 


548, 1559 :POKE 542B6,I?2:DIM A*(N256) , 


I6:IF C0L)24e:C0L=Z8:ENDIF :EXEC COLGU 


B*<N256> 


RjPAUSE 15:ENDIF 


Kg 1 18 A$^CHR*<255> :AtCN25i)-CHRt<255) -M 


NC 298 IF 1=23 THEN CQL=2B:EXEC COLOUR 


tf 2>=A* ! B*= f [ , 1 ' :W(N254>=' [ , ] ■ :»(Z 


JU 388 IF 1=5 THEN J=22:F0R I=5!i TO N4:J= 


2)=SfsB$(44)= 1 ? 1 :B$<218)= , ? , :Bt(47)=B$ 


J+32:P0KE 598+1, JjPOKE 684-1 ,J;NEXT 1 


(44) 


5M 318 IF PEEK<732)=17 THEN POKE 732,^8 :B 


TP 128 FOR I=K( T0M*:>Iffl24+44:B*fJ,J+X 


ACK=14B-flACK:P0KE ?12,BACK:P0KE 71B/EW 


1)=' [,][,]■ :NEXT I 


CK 


3F 138 REM Set-Un PMGs 


RA 328 LOOP 


JN 148 I=PEIK(184)-48fP0KE5427?,l!PMB=H 


JK 33B -- 


N254:P0KE 53277, 5f2:PflKE 423,8; POKE 7B4 


\M 348 REM Load Colours 


,IB;P0KE 785,18 


RJ 35B PROC COLOUR :J=COL:FOR 1-Z8 TO N6;J 


W 158 FOR KX6 TO HsPOKE 53248+1 .MsPflK 


=J+Z2:P0KE 5Pfl+I,J:P0KE 4B4-I,J:NEXT 1 


E 53254+1 ,Zl+(KZ2>m!NEXT I 


:EMDPROC 


JT 148 FOR 1=XB TO %liMOVE ADR(At) ,PMB+lfl 


JO 34B -- 


24+IKN254,N25i!NEXT I 


UE 378 REM DLI Data 


W 178 FOR I=XB TO ZhHOVE ADRCBt) ,FNB+I5 


EN 388 DATA 72,138,72,164,283,238,283,169 


36+Iffl254 } N254:NEXT I 


,78,2,141,28,288,189,88,2,141,21,288,1 


ME 188 REM Print Graohics 


84,178,184,64 


8X m COLOR X 1 : FOR l-U TO 191 STEP N24: 


XA 3?B REM VB1 Data 


FOR MM TO ZIjPLIIT Z8,I+J:DRWTO 319, 


LK 418 DATA 72,169,8,133,77,133,283,184,7 


I+J:NEXT J:NEXT 1 


4,130,194 


00 288 FOR 1-50 TG 319 STEP N24:F0fi J=M 




Underline = INVERSE CHARACTERS ■ [ ] s CONTROL + 


CHARACTER ■< > = INVERSE CONTROL + CHARACTER 



5€iL/^C 



30 



Page 6's New Atari Van 



PROGRAMMING 



PMG PROGRAMMING TIPS 

by John Foskett 



When using PMGs, it is normal practice 
to lower RAMTOP to provide a protec- 
ted area of HAM in which to store the 
shape data and conventionally for single line 
resolution, PMGs require 2 kBytes or 8 pages of 
RAM- In actual fact the PMG data only requires 
5 pages of RAM far storage because the 3 pages 
of RAM immediately below the missile shape 
data is always unused and is therefore wasted if 
RAMTOP is. lowered by 3 pages. It is possible 
however to protect only the required 5 pages of 
HAM leaving the 3 pages of unused RAM avail- 
able for BASIC which is achieved using,... 

RAMT0P=PEEK(1 06):POKE 

1 06,RAMTOP-5:Plv1BASE=RAMTOP-e 

If you lower RAMTOP by the conventional 8 
pages and you are not using the missiles, then 
you have 4 pages of protected RAM immediately 
below the player shape data free for use, ideal 
for storing a whole new redefined character set. 

If you are only using one player in a program, 
then use PLAYER 3, the highest in RAM so 
that you only need to protect a single page of 



RAM for its shape data storage. This will allow 
you a whole 7 pages of extra free RAM. It then 
follows that if you use 2 players in a program, 
using PLAYERS 2 and 3 will save 6 pages of 
RAM, etc. 

Alternatively, you dont have to lower HAM- 
TOP to protect your PMG data (or any data for 
that matter), you could allow BASIC to en- 
croach into the data area if you wish. The great 
advantage in doing this is that you will immedi- 
ately notice when you have used up all of the 
available RAM since it will show up on screen 
as rubbish in the PMG stripes, But you must 
however define your PMG shapes early in a 
program before defining strings otherwise the 
PMGs will overwrite the strings instead. Not 
lowering RAMTOP in this way will avoid the 
"Out of Memory" error % from occurring which 
can cause a crash- Loops and subroutines need 
RAM in which to function and if insufficient 
RAM is available for this, then stack errors can 
occur when a program is run causing a crash 
and therefore the loss of your program. • 



TEST CARD 



continued 



spots which are used to ensure accurate 
focusing, all the spots as well as the rest of 
the screen should appear clear arid sharp. It 
is much easier to set the focus by using small 
spots rather than by using lines. Initially in 
the centre of the circle is a grey scale from 
black Lo white which Is used to set up the 
brilliance and contrast adjustments and the 
colour balance to give the full range of greys 
without any colour tinge. Pressing START will 
sbwly cycle through the colours giving colour 
scales to ensure a good colour range and 
balance. Pressing OPTION returns the grey 



scale and pressing SELECT displays a range 
of colours at a mid-brilliance setting. Pressing 
HELP toggles the background colour from the 
initial black to the normal Atari blue which 
more easily shows up the flyback lines and 
also tuning inaccuracies. When blue, the 
screen should be clear without any back- 
ground roughness or flyback visible . At the 
sides of the screen are two vertical stripes to 
aid the horizontal and vertical positioning of 
the display within the boundaries of the 
screen to ensure a perfectly centred picture. 



Page 6's New Atari User 



31 




it's 



The TIPSTER 



This issue our regular Tipster Janus Matthrick^ 
cenemtraitf m some &vfflk 'Domain odvtnturcs 
avatlaStt from the fPage 6 Library* Iture art 
hundreds! ifnat ifu>usands f of^PD games avail- 
aBU of ad Jrjpuft so hois/ about sotnt hints and 
tips for these for future issues? The future is 
fttrt, it may not ht omngt But it coutd St FBI 



LIVINGSTONE 

Page 6 Adventure Set. #1 Disk 2A 
Page & Library disk #30 



The mapping system for the game is unneces- 
sarily complicated, and detracts from the game, 
however there ia a system to it - you will need 
to be patient and pcTseveje with this game. 
Some hints to help you on your way: 

In the bedroom, wear the boots and the knap- 
sack, open the book, read the book in bed, and 
type DRIFT. 

Should you find your path blocked by quick- 
sand, merely JUMP QUICKSAND. 
Catch the mouse in your knapsack, then free 
the mouse when confronted by the leopard. 
When you have the diamond, if you SAY 
SWAMI you will find yourself back in your 
room. 

Catch the viper, and free it near the dog. The 
viper is in the tree. 

You may find yourself trading with the natives, 
however, do not take the spear into the native 
village - the natives will take it as being a 
threat. 

Maybe someone could come up with a map or a 
complete solution - 1 really lost enthusiasm for 
this game because of the mapping system. A 
Tipster challenge maybe? 



DUNGEON 

OF THE GODS 

Page 6 Adventure Set #1 Disk IB 
Page 6 Library disk #23 

The aim of the Game is to escape from the 
Dungeon of the God s - here arc same hints 
arid tips to complete the game, in no particu- 
lar order: 

OPEN BOX In the first room whilst holding 
the bar 

POTION 1 and POTION 2 will make you 
either weaker or stronger - use carefully 

INSERT the copper COIN when In the casino 

WAND O will shoot lightning bolts, use It 
against the slime, but not the black dragon 

To use the magic dual WAVE DUST 

Use the LANCE against the BLACK DRAGON. 
and the FLAMING SWORD against the 
BLACK CUBE 

Collect the PLATINUM BAR. the DIAMONDS. 
and the CHEST OF THE GODS before you 
escape for maximum points 

READ the SCROLL at the RED DRAGON 

THROW the BALL at the STATUE 

FOUR the ACID at the entrance 

WAVE WAND 2 at the STEEL DOOR 

PUSH BUTTON In the STRANGE RED ROOM 
to get to "the west end of a prison cell" 

mm Pia@[g[L[giMi a 



D 



CE 



32 



Page 6's New Atari User 



To Tiny Hall 



DRAGON 
ROOM 

Diunond" 



LIBRARY 

Basil 




DARK ROOM 

SILmc CrHilurt 

Rbf 


- 


LAB 
Ml 


1 








1 


RECTANGULAR 
ROOM 

Bill 




KITCHEN 




CASINO 
Slot Midline j 










1 


DARK 
HALL 

TH.nl Cub* 




WORKSHOP 

wind a 
Tibdt 




SQUARE 
ROOM 



To Dirty ft 
-Dusty Room 



To Small Room 



STAIRS 



LARGE 
HALL 

Swori 



STORAGE 
ROOM 



STAIRS UP 



THRONE 
ROOM 



SSSKfffiSSJi 



ROOM WOW 
IVORY TABLE 



TREASURE 
VAULT 

Biult/FLitbLirai 



SMALL 
ROOM 

Potion! 



ROOM 
STEEL 



WIZARDS 
WORKSHOP 

Mafic Du*t 



To 

Small 

Chamber 



WITH 
DOOR 



!!KH:[-"5S 



MUSIC 
HALL 

rim* 



ROOM WITH 

ABRASSTA&LE 

Otto 



WEAPON 

ROOM 

Sbirld.'Lm-.r.f 



STORAGE 
ROOM 



WEND 
OF CELL 



EEND 



TINY 
PASSAGE 

Potion 1 



Dungeon of 
the Gods 



TRIANGULAR 
ROOM 



DIRTY 

ft DUSTY 

ROOM 



END 




CHAMBER 
OF THE GODS |^ 

Cheat 



CHAMBER 
OF DEATH 



BRIGHT 
CHAMBER!— I 



VERY LONG 
CORRIDOR 



HUGE 
ENTRANCE 



TINY 
HALL 



To stairs 



I 



To Stairs Up 



SMALL 
CHAMBER M 



DARK 
CORRIDOR 



LONG 
|— I DARK 
CORRIDOR 



SMALL 
ROOM 



To Room 
with Steel 
Door 



STRANGE 
RED ROOM 

Button 



To W End of 
Cell 



Page 6's New Atari User 



More Tip 



D^ 



33 



QUEST 

Fige 6 Adventure Set #1 
Page 6 library disk #23 



^OlUtlOn. Cut across country, 
mind your own business, kill the hobgoblins, 
search the hobgoblins (find something!), go 
south, go south, 
reason with the 
dwarf, yes, 7,5,9, 
go south, go cas- 
tle, go door, say 
something to the 
wizard, go door, 
attack, go cave, run 
to back of cave, 
read runes, say 
word, unlock 
door, lift stone 
door, go Into 
room,,. 




COLONY 



The following tips for Colony from Bulldog/ 
Nfastertronic were discovered on my I lard 
Drive when: they were obviously transferred 
to from an 8-blt disk but 1 can't find the 
original disk so I can't credit the Tipper, My 
apologies and thanks to whoever you are. If 
you care to admit Tt was me' 1 will happily 
give you a mention In the next Issue, Anyway 
here are the tips for Colony: 

Want lots of money fast? Order lots of 
extra seeds from the supply ship, and 
as soon as it arrives take them straight 
to the mushroom/seed store, but don't 
drop seeds. Instead, deposit 
mushrooms, and the computer will think 
you are depositing mushrooms ten at a 
time, and credits your account accord- 
ingly. This doesn't always seem to work, 
but does most of the time. ! think you 
have to deposit the seeds before you do 
anything else, once the supply arrives, 
but I'm not positive. 



XtL/^Ct 



HELP ... HELP ... HELP 



This request comes form ihe same unknown 
source as the Colony tips but if you have the 
answers, I am sure they will be of interest to 
everybody so write in. Help please with 
PANTHER. (Mastertronic). Cant get 
past the plasma wave. Too bloody Impossible, 
and seems to last forever. Can it be done, and 
if so. how? 
34 Po^e 6's New Atari User 



Remember The Tipster needs YOU 
to stay alive. Write now to: 



THE TIPSTER 

NEW ATARI USER 

P.O. BOX 54 

STAFFORD 

ST16 1DR 



PROGRAMMING 



TURBO 
TUTORIALS 



Gavan Moran 
brings you a Jew 
examples to 
illustrate the 
power oj Turbo 
programming 



PAC DEMO 

Thta demo is primarily an example of how 
the MOVE command of Turbo Basic can be 
used to animate player missile graphics. A 
few other features of Turbo Basic are also 
used and provide a good example of the way 
in which Turbo Basic simplifies programming. 

WHAT IT DOBS 

An animated 'Pacman' figure is chased 
across the screen, from right to left, by a 
ghost. Ihe pacman eats a 'power pill' situated 
on the left hand side of the screen. At this, 
the message TURBO POWER appears in 
large letters across the screen, the ghost 
changes colour to blue and the pacman 



chases the ghost back across the screen, 
eventually eating it. 

HOW IT WORKS 

Lines 1 90 to 4 1 contain the setup proce- 
dure. Player/missile graphics arc used to rep- 
resent the pacman, ghost and power pill. The 
playficld is a GRAPE HCS 19 (3+ 16) screen. 

The routine to draw the 'turbo power" mes- 
sage is contained In a separate procedure 
(lines 150 - 170) and Is called by the setup 
procedure. The TEXT command is used to 
plot the large letters - these can be quite 
effective. 

Note the use of hexadecimal numbers in line 
280, This is a helpful feature of Turbo Basic 
as it allows direct use of hex numbers in 
programs - useful for machine language prog- 
rammers. 

A DO - [.OOP loop is used to read the P/M 
data into memory. An EXIT command is used 
to escape from the loop when a - 1 Is encoun- 
tered in the data. The data is read into the 
normally unused memory area between 
PMBASE and the missiles. A number of ani- 
mation 'frames' may be stored here (up to 384 
bytes in double line resolution or 768 bytes 
using single line). 

Back to the main program which Is con- 
tained within a DO - LOOP loop which con- 
tinuously executes the main body of code. 



Page G's New Atari User 



35 









Two FOR - NEXT loops control the move- 
ments of the players from right to left and left 
to right respectively. Both these routines call 
the MOVE-PLAYERS procedure and It is here 
that the real beauty of the MOVE command 
becomes apparent. 

As 1 said earlier, frames of player data are 
stored In the unused part of player memory. 
The MOVE-PLAYERS procedure uses the 
MOVE command of Turbo Basic to transfer 
these Into the appropriate player - thus we 
have a simple but effective player/missile ani- 
mation ay stem! If this sounds familiar then 1 
recommend you read the article 'PLAYER 
MISSILE GRAPHICS' in issue 15 of PAGE 6 - 
the technique used there Is virtually Identical. 
Who said Turbo Basic had no player/missile 
commands? 

So there we have It - a simple but effective 
Turbo Basic demonstration which would 
probably have taken at least three times as 
much source code In normal Basic, not to 
mention a machine language subroutine. 
Hopefully the code is easier to read than nor- 
mal Basic too, but 1 had to compress it some- 
what to make It fit into one page. Remember. 
MOVE can be used for other tasks too - such 
as moving character sets or display lists. 



TEXT PLOTTER 

This program hopefully illustrates the power 
of some of the more unfamiliar Turbo Basic 
commands. Also, 1 hope, it should be useful 
to those people who use ATARI ARTIST or 
M1CROPAINTER software as it allows the user 
to add text to pictures which arc saved in the 
standard 62 sector picture format 

36 



USING THE PROGRAM 

The program uses a mixture of both joystick 
and keyboard commands. Initially, when 
RUN, a blank screen will appear with four 
small orange dots in the upper left hand cor- 
ner. This is the cursor - use the Joystick to 
move It around the screen. It denotes the 
position of any text that will be printed, You 
may add text by pressing the fire button and 
then typing in your text, terminated by a 
<RETURN>. To save this screen press the 
greater than (>) key. The screen will then be 
saved as an uncompressed 62 sector Me cal- 
led D: PICTURE to which a picture may be 
added using an ait package at a later date. 
Most likely, you will want to add text to an 
existing picture and this can be accomplished 
by using the less than [<) key to load a $2 
sector file called (you guessed it) D: PICTURE 
from your disk- Note that this loaded file will 
overwrite anything already on the screen. 
Text may then be added as above and the 
screen re- saved. Use keys (L.4 to change the 
colour register being used to plot the text. The 
cursor will change colour accordingly to let 
you know which register is being used [they 
correspond to the registers on the bar at the 
bottom of the ATARI ARTIST menu). The 
escape [ESC] key may be used to clear the 
screen. Note that the entire character set is 
available for plotting (Including control char- 
acters} but that the standard editing keys do 
NOT work - to delete a character, move the 
cursor back over It and type a space. 

HOW IT WORKS 

The main program is contained in the DO - 
LOOP loop- This repeatedly checks the joys- 
tick and the keyboard and calls appropriate 
procedures If action is needed. Note the use of 



m i rem mmmnmmmmmm 

NX 2 REM * TURBO BASIC - PAC DEMO 1 

HJ 3 REM * by Gavin Mar an * 

IY 4 REM * K 

vF 5 REM I NEW ATARI USER - l?9B i 

qp 6 rem mmmmmmmmmxx 

HI 7 REM 

OH LB EXEC SET_UP 

12 28 DO 

YJ 39 MOVE PM+55,PM+82i l 1 1 iPOKE HP0SP2,5f 

jPOKE CQLPHX1,72:SETCGL0R Bjfl^SETCO 

LOR 1,8,8;PAC=PM;QFFS=12 
X£ 48 FOR X=ZM TO 5B STEP -5: EXEC M0VE_P 

LAYERS :NEXT X 
RU 58 POKE HP0SF2 S 8:P0KE COLPBm,J32:SET 

COLOI M^StTCOLOa l,8,l5:PAOPH+lt: 

PAUSE 25 
ME 68 FDR X=58 TO 2BB STEP 5: EXEC N0VE.PL 

AYERSiOFFS=OFr"S-fl>35:NEXTX:PAUSE 198 
YE 78 LOOP 
ZD 89 -- 

PF Pf PROC MOVE-PLAYERS 
CM 199 MOVE PAC,PM+57e,ll:HQVE Rit33,m+A 

?S,n:PAUSE7 
NE 119 MEVE m+22,PrH57(,Il;KI)UE Fr1+44,PM 

+i?8, 11 SPOKE tTOPe.XsPQKE HPOSPl,X+IN 

KQFFS) 
YM 128 PAUSE 7 
UP 138 ENDPRQC 
JK 148 - 

ZM 158 PROC TURflfJLLOGO 
EN 149 COLOR 1 sTEXT B ,3 , "TURBQ- jCOLOR 2:T 

EXT «, 13, "POWER* 
VX 178 ENDPROC 
JS 188 -- 
FI 198 PROC SET_UP 



NB 28B RANTONPEEK( 186H256 

CX 218 RAHTflP=RAMT0P-LI24 

ES 22B POKE 186,RAmOP/256 

WI m GRAPHICS l?:SETC0LOR f ^BjSETCQLO 

R 1,8,8 
CJ 248 FOR X=RAMT0Pt512 TO RAHTQP+BMiPQK 

EX,K8:NEXT X 
WE 258 EXEC TURBO-LOGO 
HQ 26B PMWSE==*D4B7;GRACTL=t0llD;SDMCTL=* 

822F sGPRI 0R=i23iC0LP8=*82Cf ;HP0SPB=*D8 

U iHPOSP l=*D88 1 f HPQSP2=$D882 
AJ 278 RESTORE tPHDATA 
VD 2B8 OFFSETS FteRANTOP 
WC 298 DO 
IR 388 REM PMBYTE 
SW 3 IB IF PMBYTE=-1 THEN EXIT 
HW 328 POKE PMtGFFSET, PMBYTE 
DA 338 0FFS£T=0FFSET+yi 
RE 349 LW 

SI m POKE PKBAS£ l (RAnTDPy'25d) 
NS 368 POKE GRACTL.3 
EG 378 POKE SDHnL,PEEK(5DMCTL) + 12 
BL 3B8 POKE CDLPt, 248: POKE C0LPB+X1,72:P0 

KE COLJW.2,15 
WD 398 ENDPROC 

JF m - 

Ofl 418 I PMHATAeDATA 68,126,247, 127,63, 15 

,63, 127 ,255 s 12*, (58,68, 126, 239,254 ,252, 

218,252,254,255,126,68 
It 42B DATA 68,126,247,255,255,255,255,25 

5,255,126,68,69,126,255,153,221,255,25 

5,255,255,171,1 
OB 438 DATA 68,126,255,153,187,255,255,25 

5,255,05,8,8,8,8,68,126,255,255,126,68 

,9,8,-1 



Unfertile = INVERSE CHARACTERS- [ ] = CONTROL + CHARACTER -< > = INVERSE CONTROL + CHARACTER 



Page B's New Atari User 



Page 6*s New At&r( User 



37 



ok I rem mmmmmummmm 


m 2BB ENDPRDC 


EW 2 REM HURBO BASIC - TEXT PLOTTER I 


Al 298 -- 


HJ 3 REM S by Gavin Horan * 

TV i PCH i * 


CY 310 PflGC S/WLFILE 

f""ip ■Tift nnni u -i -n a in n t rt-n irt*™« 


IT ^ HLn t i 


FH 3 IB OPEN 1)1,8,8, D:PICTURE 


VF 5 REN S NEW ATARI USER - IPPB K 


HD 320 BPDT IL, SCREEN, 748ft 


QP 6 REM mimmmim*H33EHm3E* 


LF 338 CLOSE tl 


nm ? rem 


VT 348 ENDPRDC 


OH IB EXEC SETJJP 


JO 350 -- 


12 20 DO 


LU 3(58 PROC CHECILSTICK 


IX 21 EXEC CHECK-STICK 


HI 370 S=ST1CK(8) EXOR 15 


GP 25 IF PEDf™)0255;6ET KEY 


DA 380 IF SO0 


AE 48 IF KEY- ii 


YI 3P8 XPDS=XPOS4':Si8>8)-(a4)0) + (XPOSai 


ZD 5fl EXEC LOAD-FILE 


) -UPOS) 151) :YP0S=YP0S-< SU>B> +( &2)0) 


UL 6ft ELSE 


+(YP0S«1)-(YP0S)]8D 


AT 78 IF KEY=dl 


XR 4BB COLDS PIXEL: PLOT LX,LYiCOLOR PIXEL 


GB SB EXEC SAYE-FILE 


1;PL0T LX+7 J L\:CQL0R PIXELZiPLDT LX.LY 


uo n ELSE 


*7:C0LDH PIXEL3:PLDT LX+7,Lt*7 


PH IBB IF CKEY>47 AND KEY<52) THEN CURSOR 


RM 418 EXEC PLdLCUflSOR 


*KEY-48 


IP 428 ENDIF 


IK lie ENDIF 


DT 43B IF STRIG<B)3ffl THEN EXEC PLOT-CHAR 


IH m ENDIF 


ACTER 


XS 138 POKE 764,255:END1F 


UU 448 ENOPROC 


RE HB LOOP 


JP 456 ~ 


JM 158 -- 


1*1 4*8 PROC PLOT-CHARACTER 


UE 168 PROC PLUT.CURSOK 


m 478 GET CHAR 


NK 178 LOCATE XPOS ,YPQS, PIXEL: LOCATE XPOS 


FV 488 WHILE 0HRO155 


+7,YP0S , PIXEL 1 : LOCATE XPOS r YP0S+7, PIXE 


PB 435 TEXT XPOS 1 YP OS, CHR*( CHAR) 


L2:L0CATE XP0S47,YP0S+7,PIXEL3 


LN 4?B XPOS=XPOS48:1F XP0SM52 THEN XPQS= 


HC 188 COLOR CURS&RiPLOT XPOS ,YPOS: PLOT X 


152:EXIT 


P0S+7,YP0S:PL0T XPOS l YPOS+7:PLOT XPOS+ 


RL 588 EXEC PLOT-CURSOR 


7,YP0S+7 


NO 518 GET CHAR 


MR l?fi LX=XPOSiLY=YPOS 


MY 528 WEND 


m 288 ENDPROC 


VT 530 ENDPRQC 


JF 218 -- 


JO 548 -- 


HC 228 PROC LQMlFILE 


FE 550 PROC SET_UP 


EV 230 DPOKE 88 .SCREEN: POKE 87,15 


W 568 GRAPHICS 31:SCREEN=DPEEKTO 


DM 248 OPEN ill ^^flj'DjPlCTURE" 


UY 578 XPQS=J!B:YPOS^B : CURSORS U EXEC PLO 


FY 258 BGET tl,SCREEN,7dBI 


T_CURSOR 


LK 248 CLOSE It 


HD 580 ENDPRDC 


m 278 EXEC PL0T_CURB0fi 




mmw = INVERSE CHARACTERS ■ [ ] s CONTROL + 


CHARACTER • < > = INVERSE CONTROL + CHARACTER 



38 



Page 6's Neu? Atari User 



GET without needing an OPEN and the way 
CLS #6 is used to clear the screen. Proce- 
dures LOAD-FILE and SAVE -FILE use the 
RC Err and BPUT commands to read/write the 
screen data from/ to disk - much handier 
than machine code CIO calls and much 
quicker than the usual PUT/GET method. 
Procedure CHECK-STICK uses the binary 
manipulation facilities of Turbo Basic In con- 
junction with a little boolean algebra. Note the 
use of the EXOR (Exclusive OR) and W [bin- 
ary AND] commands to read the stick directly. 
The result is a compact, quick method of 
Joystick reading, NB. Touch tablet users may 
wish to change the code to read STJCK[1) in 
order to use the second joystick port to avoid 
having to swap the tablet and the joystick. 
PLOT-CHARACTER uses the TEXT command 
to plot the text on to the graphics semen - 
another useful Turbo Basic command. 

Well, that's about it. Because this program 
was written within the constraints of having 
to fit In a page, there are quits a few features 
missing. How about aP/M cursor (could be 
controlled using MOVE command), memory 
save (again using MOVE command} , RAM- 
DISK support on 130XE or 256K 800XLs, 
multiple fonts and different text dlrcctlons- 
?Plus the excellent PIC LO ADA code printed in 
issue 20 could be added in order to enable 
direct loading and saving of ATARI ARTIST 
screens. And of course, the program can then 
be compiled for even more speed! 



MINI CHARACTER 
SET EDITOR 

This program is a little too long to Include in 



the magazine so you will find ft on the Issue 
disk, I have not written a full set of docume- 
ntation, however there follows some short in- 
structions on how to use the program. 

When the program is RUN, a status line at 
the top left hand comer of the screen Informs 
you of the ASCII no, Internal no and actual 
character being edited. Below these is a char- 
acter grid showing the character which you 
are editing, A lit square on the grid represents 
a lit pixel In the character and a dot repre- 
sents an unlit pixel. To the right of this Is a 
large representation of how the character 
looked before you started editing it. Moving 
the Joystick will cause a star shaped cursor to 
move around the grid. Pressing the fire button 
will toggle the pixel under the cursor either on 
or off. A list of commands is shown below and 
these are selected by typing the key which Is 
highlighted In inverse texL Commands are: 
Load - loads a character set off disk, This set 
MUST be called CHSET.FNT. If this is not 
present the program will crash. Save - Saves 
the set currently in memory to the disk In a 
fUeeallcd CHSET.FNT. Getchar (ASCII) - 
allows you to type the ASCII number of the 
character which you wish to edf t, e.g. 6S will 
get 'A' to be edited on the grid, Getchar (type 
key) - allows you to get a character for editing 
by typing it's equivalent key on the keyboard. 
e <g Typing H" hi this option will bring the 
character H up for editing. Futehar - Puts the 
character being edited back Into the set. This 
must be done In order to permanently change 
the character as the character Is edited In a 
separate buffer. Default - Returns the charac- 
ter set to It's default (Internal) stale. 

This program hopefully demonstrates how 
Turbo Basic simplifies programming compli- 
cated tasks and how It's Increased power 
allows shorter code to be written. 



Page 6's New Atari User 



39 



PROGRAMMING 



DISK DIRECTORYMOVER 



In response to a letter from James Austin 
In Mailbag of Issue 80 which made a few 
suggestions for updating ray Disk Direc- 
tory Mover published In Issue 79, 1 present 
Disk Directory Mover Version II. In his letter, 
James suggested that there should be a 
means of going direct to the menu bypassing 
the formatting stage so that all the flics do not 
have to be copied in one session, James also 
suggested that there should be a means of 
listing the directories of both the standard 
disk and the modified disk from the menu. 
For a full explanation of the Disk Directory 
Mover, please read this article in conjunction 
with the associated article published in issue 
79 of New Atari User. 



DIRECT MENU ACCESS 

Direct access to the menu bypassing the 
formatting stage presented one major prob- 
lem, that of remembering the position that 
the directory had been moved to. Obviously, 
the new directory position must be entered 
somehow before the menu can be accessed so 
that the program can he set up correctly to 
suit a previously modified disk. Entering tills 
vja the keyboard either from ones memory or 
from notes could prove error prone because it 
Is so easy to make mistakes. Some means of 
achieving this reliably was necessary and to 
this end, a disk data file was chosen. 



Tb access the menu directly, a prompt to 
press the TAB key is given from the initial 
screen along with the directory positioning 
options. After the TAB key has been pressed, 
the data file is read and only if found on the 
disk currently in the drive will direct access to 
the menu be enabled. If the file Is not found, 
then an error will result and OPTION must be 
pressed to exit denying direct menu access. 

After a disk has been formatted and pre- 
pared by the program, a prompt Is given to 
Insert a standard (normal directory position) 
disk into the drive to receive the data Ale 
DIRMGVE.DAT which records the position 
that the directory has been moved to. To ac- 
cess the menu directly on a subsequent occa- 
sion, it is then only a matter of running the 
program with the disk containing the pre- 
viously written data file in the drive. 

The data file DIRMOVE.DAT Is used to re- 
cord 2 pieces of information, firstly the new 
directory position and secondly the format 
density of the modified disk for information 
purposes on the menu screen. 



LISTING 
THE DIRECTORIES 

The menu of the original version of the Disk 
Directory Mover had the options to lock/un- 
lock files and to write with or without verify as 



40 



Page 6's New Atari User 



VERSION II 



options 7 and 8. These have been moved to 
op lions 8 and 9 respectively to version 11, 
Option 7 is now used for directory access. 
Upon selecting option 7, a menu is presented 
from which "S" Is pressed to list the directory 
of a standard disk and "M" is pressed to Ust 
the directory of the modified disk. But of 
course, the appropriate disk must be In the 
drive otherwise data (rubbish) will be display- 
ed Instead. 

The directory- is displayed in 2 columns of 16 
file names per column over 2 screens display- 
ing If necessary all 64 file names. If the direc- 
tory contains 32 flic names or less, then only 
a single screen is required and OPTION Is 
pressed to exit. If the directory contains more 
than 32 file names, then a second screen is 
necessary and START is pressed to list the 
remainder of the directory on the second 
screen or OPTION is pressed to exit. 



OTHER MAJOR CHANGES 

The initial screen has been slightly altered 
and the VB1 routine has beert modified to 
flash the arrow used to select the new direc- 
tory position and to flash the data entry cur- 
sor. The program now amends the disk's 
VTOC sector(s) before writing the DOS, SYS 



by John Foskett 



file. In the original version after pressing 
ESCAPE/OPTION to cjrit from the menu back 
to the initial screen, '"Y" had to be pressed to 
confirm the request since It was not possible 
to re-enter the menu. Exiting is now actloned 
directly upon pressing ESCAPE/OPTION. 



USING THE PROGRAM 

A master disk should be prepared for the 
Disk Directory Mover as stated In the original 
article published in issue 79. To avoid confu- 
sion when copying files over more than one 
session, it is recommended that the associ- 
ated disks arc kept in pairs, that is the mod- 
ified disk should be kept with the standard 
disk which contains the files to be copied. The 
standard disk should also contain the data 
file DIRMOVE.DAT written to it during the 
preparation of the modified disk. In this way. 
several modified disks could be prepared and 
have files copied to them In, the same session 
without confusion. 



A WORD OF WARNING! 

Do NOT select option 8 from the menu to 
lock /unlock files If a standard directory disk 
is in the drive since It could corrupt the disks 
data. Tills option writes Into the moved direc- 
tory position to lock/unJbck flies which could 
be in data sectors of a standard disk. The 
Disk Directory Mover has no way of determin- 
ing whether the disk in the drive Is a standard 
disk or a modified disk so please be careful! • 

The Disk Directory Mover program can he 
Jbund. on the Issue Disk 



Parje 6's New Atari User 



41 



Features 

and @™d@M! 



USER vs PROGRAMMER 



Joel Goodwin 
discusses the ways 
in which the user 
might see things 
differently to the 
programmer 



The programmer normally enjoys a 
close relationship with the computET- 
This, of course. Is essentia] if the 
programmer Is to get the best out of the hard- 
ware. The user, however. Is sometimes ex- 
cluded from this relationship and can get well 
and truly left out In the cold- What might 
appeal to the programmer may not suit the 
user so well. The user looks for convenience 
and practicality, while the programmer looks 
fur internal efficiency and finesse. 
Above all, the computer must communicate 
effectively with the user and If a program is 
not written to achieve this then all of the work 
Invested in it can be wasted. This article is 
about designing software for ordinary people 
who are often forgotten or ignored during the 
creation of a program. 



WELCOME 
TO THE MACHINE 

Just to demonstrate how important design 
can be. consider a few examples. Do you pre- 
fer a text menu with keyboard input or a 
windows system driven by a mouse? Are you 
enthusiastic about BASIC giving you the error 
message "ERROR- 162' or would you prefer 
Disk Full? Do you really enjoy learning CTRL 
key commands for utilities such as Textpro? 
Is a blank screen reassuring or would you 
prefer a 'Please Wait - Initialising" message? 

The subject being discussed here has many 
names. A common term is "user-friendliness*. 
De Re Atari has a wonderful appendix on it 
ca]5ed 'Human Engineering'. A modem term Is 
'Human -Computer Interaction' (HO). Whatev- 
er name you care to use, it is something that 
should always be considered when writing 
programs. There are. unfortunately, no hard 
and fast rules about the best way to design 
software; as De Re Atari puts It, It is 'an art, 
not a science'. The aim of this article is not to 
a up ply answers but to encourage program- 
mers to ask themselves questions about what 
the user really wants. We'll discuss some 
topics and examples to illustrate the types of 
problems and the solutions that exist. 



42 



Page: &'s Mem Atari User 



THE LEARNING 
CURVE 

What Is the first thing you do when you get a 
new piece of software? Normally, you would 
probably just shove in the new cassette/disk 
and boot it - only later if necessary would you 
look at the instructions. Everyone has an in- 
stinctive loathing of manuals, so a program 
will be more successful in a user's eyes if it is 
designed to minimise the importance of a 
manual. 

Software, to some extent, should maintain 
independence from the manual. A program 
should be able to lead, if not teach, a user. If 
a program forces a user to read the accom- 
panying instructions, the user will become 
disenchanted with the program from square 
one. How is this avoided? There is no single 
answer, but it would seem sensible to design 
a program which keeps the user well-infor- 
med at all times: What options are available? 
What exactly do they do? If an error occurs, 
what docs It mean and how do you remedy it? 

The problem with this Is that the computer 
does not possess an infinite memory capacity 
In which to store bags of informative text 
messages. What is Important is a balance. On 
the DOS 2.5 menu, the Option 'A, DISK 



DIRECTORY' Is sufficient. I don't need 'Press 
"A" to call up the disk directory, which is a list 
of files on the disk currently located in the 
specified drive'. Too much information can be 
as bad as too little; it can impede progress as 
the user cannot isolate the key points. A 
HELP function can assist in allowing the 
user to control the level of information being 
received. 

The faster the user can pick up a program, 
the more the user will like it. Although com- 
municating with the user is very Important it 
Is not the only factor which can affect the 
learning curve associated with a program. 
Consider the method of requesting or input- 
ting data In a utility program, [f you keep a 
consistent approach to input (e.g. all input Is 
through a cursor controlled by Joystick) then 
the user always knows what to do. An Incon- 
sistent approach can confuse; 1 have seen 
many a program which has some menus 
which act on a single keypress and others 
which require RETURN to be pressed after the 
letter. It Is all very well telling the user to 
press RETURN, but why should the user have 
to? A single menu subroutine can be useful 
here. (Note: De Re Atari advises that the 
keyboard should only be used as an input 
device If unavoidable, e.g. filename entry.) 



CLARITY 

Graphics can be a burden as much as a 
blessing. Attractive graphics may simply turn 
out to be clutter where the essential details 
are not highlighted, or worse, are obscured, 
Colour, symbols and animation can all en- 
hance the display but care mu3t be taken to 
avoid overuse, I recall Clayton Walnum wrote 
in ANALOG magazine about an occasion 
where he had used character set cycling to 



Page 6's New Atari User 



43 






produce pulsating orbs around the display of 
a text adventure. He'd slaved over the routine 
arid graphics for some time. Once it was 
working, he showed it to someone (his wife, if 
memory serves) and he was told that It looked 
very nice... but it was distracting. Eventually 
he realised that he had to take the animation 
out: it was ruining a fine text adventure 
(Clayton did go on to write an ANALOG article 
called TextuaJly Graphic" on the same subject 
as this article). 

Something that is hard to come to terms 
with is the need to remove a perfect piece of 
code purely because It doesn't took right. It is 
worth it, believe me. An overuse of graphical 
variety will Just look like a uniformity of 
chaos, 

Sometimes simplicity is the best approach. A 
nice example Is John Foskett's "Sound Selec- 
tor' (NAU Issue 76} which features little more 
than a screen full of text However, the prog- 
ram slightly modifies the display list and uses 
DLIs to stratify the screen and this works very 
well. Not only does it introduce clarity, but it 
brings life to what could easily have been a 
dull text display. 

Symbols are good to use if there is some 
natural connection between the symbol and 
its meaning. For instance, a pair of scissors 
can be used to represent a 'cut' option, A 
shield icon can be used to label a bar of shield 
energy in a game. Whenever devising a set of 
symbols to represent concepts or objects, try 
to develop symbols which seem natural, 
some tiling anyone could understand - or at 
least within the general context of the prog- 
ram. Think how you might express the fol- 
lowing: 

]) Music 
U) Time 
til) Cat 
iv) Money 
v) Save 



Of these, (v) is probably the most difficult. 
'Save' doesn't appear to have a natural sym- 
bology attached to it. Something more inven- 
tive would be required: one way of expressing 
It would be to have a disk with an arrow 
pointing to it Note that this symbol Is safely 
dependent on context. 

The last thing I'll mention in this section is 
character sets. Make sure that the set you 
use for text is easy to read. 1 have a copy of 
'Lemmings 2' for the Sega Mega Drive (1 make 
no excuses for my heresy) and the text font It 
uses is appalling. 'C' looks like G"; M" like W 
and T like 'J*. This font Is used to display 
passwords which are 20 letters long and can- 
not be found in any dictionary I know of. 
Make one mistake writing down the password 
and the whole thing is invalid. This font does 
not make me very happy. 



THE FRUSTRATION 
FACTOR 

Staying with 'Lemmings 2', there is a 'Nuke' 
option you can activate if you feel you cannot 
complete the level. You move the cursor onto 
a mushroom cloud icon and press the button 
twice - this is good for safety. However, you 
then have to wait for every single lemming to 
explode, each with a 5-second timer on their 
head. How pretty and wonderful... the first 
time. After that, it becomes annoying. So you 
get used to hitting the 'Fast Forward' Icon 
which speeds things along. But this means 
every time 1 need to restart the level, which 1 
need to do a lot, I have to press the button 
three times with a deft joypad movement in 
the middle to change icons ■ and 1 still have to 
wait a short while. When there are 50 lem- 
mings on the screen to explode, things tend to 
slow down a little. Forcing this upon me every 



44 



Page 6's New Atari User 



single time really puts me off playing. Many 
other games have the same problem: why 
should I have to wait for the death march to 
play? Or for the ambulance to come on? Or 
for the car to explode into many beautiful 
pieces bouncing around the screen? All I want 
to do is get on with my next go. Any program- 
mer's idea of fun is not welcome when It 
strongly interferes with gameplay. Repetition 
In this way can kill a promising program from 
the outset 

An extremely common problem is the 
dreaded temporary text message. That is, text 
which appears and takes either too long to 
disappear or disappears too early and you 
missed half of It (watch the Chart Show on 
ITV for a demonstration of this, especially as 
those messages disappear from the END 
first). Unless It's a message of few words, my 
advice is always use a prompt. Never try to 
estimate how long the user will need to read a 
mass of text; Just use PRESS SPACE BAR TO 
CONTINUE' or something In that vein. For the 
same reason, I detest long scrolling messages 
- 1 could quite easily read a large page of text 
which would be a lot quicker with a lot less 
eyestrain. Yes, 1 am the Victor Meldrew of the 
computer world. 

These are indirect examples of communicat- 
ing too much to the user, or at least too 
slowly. Problems of frustration are not always 
of this type, though. Most of this article has 
revolved about the communication of infor- 
mation between user and computer. Games, 
especially, suffer from problems unrelated to 
information per se. There are many games, for 
example, which need a character to be posi- 
tioned in EXACTLY the right place to jump a 
hole and not crash into something on the 
other side. One pixel off and I'm dead. This is 
not good gameplay. This is sadism. 

Let me describe to you a problem I have had 
to deal with and how t resolved 1L When 1 
wrote the Citadel (NAU issue 74 disk bonus) I 



faced the problem of what speed to give the 
player's character. The character Jumps from 
position to position: as one Jump too many 
can ruin the player's progress, judging the 
correct time delay between moves/jumps was 
important However, a puzzle game like the 
Citadel attracts a variety of players: some will 
have arcade game backgrounds adept at Joys- 
tick use, others will be into more cerebral 
games which arc not demanding in terms of 
joystick reactions. The former will like a fast 
speed, the latter a slow speed. So a single 
game speed would not suffice - it was clear 
that I had to supply a speed option on the 
title screen- 
Orson (NAU issue 7 1 } faced a similar prob- 
lem but it is not so pronounced. In Orson, the 
character can be seen to walk from one posi- 
tion to the next and doesn't Jump, This allows 
the player to gauge when to release the Joys- 
tick and a speed setting is not necessary, 
I lowever, the story does not end here. 1 have 
since realised what the ideal solution is which 
avoids any effort on the part of the player - a 
joystick Interface which prevents continuous 
movement That Is, if the Joys tick is pushed 
left then the character would move left ONCE, 
The player needs to return the stick to neutral 
then push left again to move the character 
another step. This totally eradicates the 
movement problem: the character automatic- 
ally moves at whatever speed the player is 
capable of. This solution requires more work 
than both the Citadel and Orson implementa- 
tions but it would be better by far. 



CLOSING NUMBER 

There is an awful lot to consider when de- 
signing a program. I've tried highlighting 
some areas, even discussed some specific 
problems, but this subject is just too large to 



Page 6's New Atari User 



45 



condense into a small article. Let me re-Iter- 
ate a few Important ideas; 

• Put yourself In the user's shoes. If this 
Involves extensive testing by yourself or 
a friend [soon to be ex-) then so be It! 

• The user learns quickly when a program 
behaves In a consistent way across a 
variety of circumstances. 

• Don't be afraid to remove portions of 
code because they don't work well with 
the user. Your program will be better For 
Its 'lobotomtsation'. 

• Try to talk In a language tine user under- 
stands whether by symbols or text 

It Is Instructive to look at other people's 
programs and think about what annoyed you 
about them. Learn from this; don't make the 
same mistakes yourself. It can also be useful 
to consider what you liked best about a 
program. 

The subject of HCI is receiving a lot of atten- 
tion these days and many books have been 
written about it. There is a vast range of 
theories and practical approaches concerning 
the design of the interface with the user and I 
have found a little reading on the side has 
helped a lot The Open University book 
'Human-Computer Interaction' (Jenny Preece 
et at. ISBN 0-201-62769-8] provides an ex- 
cellent comprehensive introduction to modern 
HCI problems and solutions; if not wholly 
applicable to the Atari, It will certainly get you 
thinking, 

I hope iVe provided some food for thought If 
anyone disagrees with anything presented in 
this article then drop a line to Mailbag - I'm 
sure they'll be pleased to print your com- 
ments . Good lu ck on your next program! • 



SUPERCIRCLES 

continued 



needed. Also, the subroutine could probably 
be extended to become a "su pcrcllipsc" sub- 
routine. 

Perhaps this Isn't an "optimum" method and 
someone else has a better Idea, which relies 
only on integers perhaps. If so, please write to 
NAU, Id love to hear of it! 



MATHEMATICS! 

The equation of a circle about the point (0.0) 
with radius r is given by: 

tf + y 3 -!* 

Differentiating this equation with respect to x 
yields: 

2x +■ 2yy' = 

We can approximate the derivative term y' by 
using small changes In x and y. denoted by 
Dx and Dy, So this equation can be approxi- 
mated by: 

Dy 
2x + 2y - = 
Dx 

Re-arranging: 

x 
Dy = - - Dx 

y 

So if we move along the circle by Dx in the 
x-dtrection, then we need to move by Dy, 
specified by this last equation, in they-direc- 
tion. If we restrict ourselves to Dx=l, then 
this tells us exactly where to put the next 
point on the screen display. This will not work 
if you have the correct next point vertically 
adjacent; if we increase with Dx= 1 we will 
only see one point and then advance to the 
next column. We should now switch to using 
Dy= 1 and determining the corresponding Dy. 
Fortunately, by using symmetry we stop as 
we reach such a point. • 



The CLASSIC 



46 



Page 6's New Atari User 




Z09& 



. I e return to normal service 
*IAf this issue with yet another 

f V random selection taken, from 
the public domain. 



READ ALL ABOUT IT 

Codcsmiths newsletter Reader 

[DS#48] by Sean Fuckett is a program that 
will allow you to produce a classy looking disk 
based newsletter. The CNR reads standard 
text files into which commands arc inserted to 
control the features of this program. The CNR 
automatically word-wraps and microspace 
Justifies the text for you. 
The commands available are as follows. 
Loadfortt - Loads a font into one of the two 
font buffers available. Proportionality infor- 
mation is derived from the font data itself 
Select Font - Selects either one of the two 
fonts for printing by the program. 
Watt for a Key - This pauses printing until 
you press an key. Whenever the computer is 
waiting for a key* the border around the 
screen becomes a different colour than the 
background. 

Page Break - Halts the printing, and wails for 
a key. CNR will wait for a key If the screen is 
about to scroll, so this is useful only as a 
chapter break or something like that 
Clear Screen - Instantly clears the screen and 
Starts printing from the top. 
Set scfieen colours - The first parameter sets 



by 

Austin Hillman 



one of sixteen possible hues for the screen 
colour. The second parameter is the intensity 
of the screen. The third parameter is the 
brightness of the text itself. 
Load Screen File - This clears the text screen, 
sets a graphic mode, and loads 76B0 bytes of 
Image data directly so the screen. The four 
colour registers are stored as the last four 
bytes of the file in Mieropainter format. After 
loading the image, the CNR waits for a key, 
then returns to a clear text screen and con- 
tinues printing. 

Global Bonders and line elpactno - Sets three 
Important global settings. Left margin, right 
margin and line spacing. 

Menu Option Definition - Sets the option string 
referred to by the number parameter to the 
filename parameter. This, when combined 
with menu selection makes this a powerful 
program. 

Menu selection - This command waits for a 
number key to be pressed. The number must 
be greater that or equal to low, and less than 
or equal to high. The number pressed is 
stored Internally. X when used in place of a 
filename means use the filename we stored 
with the menu option definition command, 
instead of an X. 

Execute sub-file - Reads and prints and ex- 
ecutes a subroutine-like file. 
Top ofjtte - This re- executes the current file. 
Chain tajile - Similar to execute sub-file, 
except that the current file is ended, and the 



Page 6's New Atari User 



47 



new file replaces it. 

{/"statement - Skips the next line If the num- 
ber key pressed was NOT the parameter. 
End fie - This Is not required at the end of a 
file, it Just serves for a useful way to exit a 
subroutine or loop when you test with an if 
command. 

Define a lobet • This marks a position In the 
flic that you will be able to Jump to with the 
next command. 

Jump to label - This causes the CNF to skip 
all Instructions and text until a label Is found 
that matches the jump command. Note this 
will only jump forward. 
Make sureftte exists - This command will 
check lor the existence of a file (or X]. If the 
flic does not exist, the CNR waits for a key. 
then re-checks for the file. This command will 
not allow the CNR to continue until the file it 
wants is found. Use this command to verify 
that the user has switohed disks if you asked 
htm to. 

The example newsletter provided is a tutorial 
on the commands listed above and how best 
to use them. Several digitised picture files arc 
also included. 

Even thought his appears to be an excellent 
piece of software 1 have not yet come across 
any disk magazine that uses the program, 
which seems a pity. 



GOOD GAME 

Ultra Tetrts f#l&0) is alurbo-BASIC ver- 
sion of the popular falling bricks game written 
by Tim TruesdaJe. in this version the pieces 
are rectangular and composed of three col- 
oured squares. The object is to get three or 
more squares of the same colour into horizon- 
tal, vertical or diagonal lines. 

The first five levels are selectable, but you 

40 



have to beat the next five by skill alone. Con- 
trol is by keyboard for left, right- rotate, drop 
and pause. A high score table is provided, as 
is a good looking title screen. Released on a 
shareware basis, the registered version has 
instructions on how to unlock the hidden 
features of this game. If you like Tetris I think 
you will And this a good variation of the 
original. 



HELPING HAND 

Extended Atari BASIC (#186) by Robert 
Berry adds extra commands and features to 
standard Atari Basic, It is suitable for the 

XL/XE only as it utilises the shadow ram in 
these machines and thus only uses 3k of free 
ram. 

On loading the standard screen appears with 
an extra 25th line at the top telling you EAB 
is Installed. Also on this line a clock counts 
the elapsed time until it is set to the current 
time by the appropriate command. The extra 
line will remain active until a graphics call is 
made. 

The program is disabled when DOS is called 
and so adds 10 DOS commands to reduce the 
need to do so. They are DlRectocy. LOCK, 
UNLOCK, DELETE, RENAME, Write DOS, 
FORMAT. SINGLE density format BSAVE and 
BLOAD. Another 1 1 commands help with 
Basic programming including a PROTECT 
command which will 'lock up' the computer to 
keep it safe from interference. As well as 
AUTOnumbcr. RENumber, Variable Name 
Table, VERIFY, DEC, HEX, SIZE, LOMEM, 
ERROR and CONVERT commands. 

Special function commands contml the cas- 
sette, printer and 1 30XE rambank as well as 
providing coldstart and Basic off from the 
keyboard, Also available is a Joystick control- 






led cursor, flashing if you prefer, 5 predefined 
and 7 user defined keys for your convenience. 

Most of tine extra commands may be utilised 
by a Basic program via an XI O call. Sample 
programs are provided to demonstrate the 
CONVERT, FLASH. ERROR and BANK com- 
mands. Full documentation of all commands 
and features is provided 

Extended Atari BASIC is a neat Implementa- 
tion of many useful commands and utilities 
for the Basic programmer. That being said, 
Turibo-BASiC has now superseded this prog- 
ram and is clearly the first choice for serious 
programmers. 



A NEW LOOK 
FOR OLD FONTS 

Glyph Font Editor (#312) written in Ac- 
tion! by Jack Prevost is a fully featured font 
editor. The layout Is clean and simple with a 
font display, edit, window and menu table. 
The menu has 2 1 commands which are selec- 
ted by arrow key or joystick, the edit window 
is also controlled by either method. Two new 
fonts plus the system font can be held In 
memory at once and can be swapped at will. 
The system font is for reference only- 
Creating a new font or altering an existing 
one is simplicity itself, but if you are feeling 
lazy, nine new fonts are Included to show you 
what can be achieved with this program. 
Some handy utilities have also been provided 
along with full instructions. FONT1jOAD.COM 
allows SpartaDOS users to load a non resi- 
dent font from the command line. ROSETTA- 
.COM converts any font Into BASIC data 
tables or an Action! data block for use in your 
programs with the FONT.LSTor FONT, ACT 
loader programs supplied. 



WRITE ON 

Chick Scratch (#147) by Robert Chick is 
a word processor for the XL/XE, On bootup 
you are presented with a red screen and a 
flashing cursor with a command line at the 
bottom. Editing commands are the usual 
CONTROL letter or OPTION plus CONTROL 
letter combinations. Print format commands 
are SELECT letter combinations. They are set 
up to suit the XMM80 1 printer but can be 
changed to suit any other printer. Commands 
are summarised on five help screens available 
by pressing CONTROL H. The usual mlniDOS 
screen completes the package. 

Needless to say if the default settings are not 
to your liking they may be altered. The custo- 
mising program provided allows you to per- 
manently change the default settings for text/ 
screen colour, upper/lower case, insert/over- 
write mode t screen width, print format, key 
click and text/program mode. 

The full documentation supplied provides all 
you need to know. It closely resembles other 
word processors like Speedscript and is thus 
easy to use if you arc already familiar with the 
layout, but even for the beginner it is a good 
choice, it may lack some of the features that 
more expensive word processors have, but it 
is a very competent program as I have disco- 
vered while using it to produce this article. 



RATINGS 

CODESMITHS NEWSLETTER 

READER (DS#48) 
ULTRA TETRIS (#190) 
EXTENDED ATARI BASIC (#186) 
GLYPH FONT EDITOR (#212) 
CHICK SCRATCH (#147) 



Page 6's New Atari User 



Page 6's New Atari User 



60% 

70% 
50% 
«0% 

90% 

49 





TO AMERICA 

VIA 
THE INTERNET 



I 



John S Davison 
continues his 
exploration of 
the Internet 




so 



n Lhc last Issue we looked at how my son 
John jnr, used the Internet to help 
arrange his emigration to the USA, Sever- 
al months after his departure we decided to 
visit him at his new home near Chicago. Also. 
we have friends in Fort Worth, Texas we'd not 
seen for severs] years, so we decided to In- 
clude them on our Itinerary. Following John's 
success with the Internet wc thought we'd use 
it to plan our trip too. 
The major expense of any trip to the USA is 
the air fare, but there are lots of on-line 
places you can look to find special offers on 
flights (and complete holiday packages if you 
need them) to help keep the cost down, For 
instance, if you're a CompuServe member the 
command GO HOLIDAYS will take you to an 
area that claims to have 70,000 holiday and 
flight deals on offer. We have an old friend 
who works in the travel industry who can get 
us really good deals on flights to the USA, but 
unfortunately he had no tickets to Chicago 
available In the timeframe we wanted. The 
best (lights he could offer were from Gatwlck 
to Houston, Texas, so we decided we'd start 
our trip in Texas, A quick scan of prices of 
similar flights on the Internet and Com- 
puServe showed our friend's oiler beat the 
on-line deals, so we booked through him. 
One small problem - Houston is about 250 

Page &'$ Neu? Atari User 






miles from where we really wanted to be - the 
Dallas/Fort Worth (DFW) area - so we needed 
an internal flight to take us there. A quick 
visit to Yahoo (www.yahoo.com) pointed us at 
Southwest Airlines (www.iflyswa.com) who 
were advertising special pru motional deals an 
flights within Texas, The fare to DFW was 
very reasonable and 1 could have booked It 
on-line there and then. However, 1 can't yet 
bring myself to trust my credit card details to 
the Internet, so decided to book through a 
travel agent instead. Unfortunately, we then 
discovered that South West Airlines don't sub- 
scribe to the booking systems used by UK 
travel agents, so we couldn't book directly . 
The agent checked what else was available, 
and found that American Airlines were also 
doing special promotional deals on Texas 
routes and could actually substantially 
undercut South West's low ticket prices, so we 
booked with them Instead. The total cost of 
the two flights to get us to DFW was less than 
any direct flight I could find, so we were doing 
OK so far. 



t» Nrc*£-iPE lA-miiikl 




Page 6's New Atari User 



PLANE OR TRAIN? 

It's around 1 100 miles from Fort Worth to 
Chicago, and the sensible way to travel be- 
tween them is obviously by air. So did we do 
the sensible thing and book these flights too? 
Oh, no! We had this crazy idea of going by 
train instead. The thought of travelling across 
Texas. Arkansas, Missouri, and Illinois using 
a mode gf transport unknown to most Amer- 
icans was appealing as It added an extra 
clement of adventure to the trip. So, U was 
back to Yahoo again to find details of train 
companies. We ended up at Amtrak's web-site 
(www.amtrak.com}, the company that now 
handles virtually all long distance rail travel 
in the USA. 

The site described all Amtrak's long distance 
routes, and to our delight we discovered they 
offer special USA visitors' rail passes. These 
were Just what we wanted - unlimited travel 
by train for IS or 30 days In various zones of 
the USA The one which would get us from 

Fort Worth to Chi- 
cago and back 
again cost the 
equivalent of 
about £ 130, a real 
bargain. This co- 
vered "coach class'" 
seats only, with 
basic or de-luxe 
sleeper cabin 
accommodation 
available at {con- 
siderable) extra 
cost. Travel would 
be on the 'Texas 
Eagle", a train that 
runs from San 
Antonio in south- 
west Texas via 
Fort Worth all the 
way up to Chicago. 
The web-site also 

51 



i-4 L. ) IrSKIWi L >1 F'(LT,J MS Ukj rinr; 




■ MEUEJH IMCLI-i. |#^1iOiP motion. d'-MMi*] 



wta:iL'jjgi?-fl.*c^'*trf i*riR 





E«55^ 



showed the train's 
timetable, so we 
could work out 
our other travel 
plans around It, 
These long dis- 
tance trains only 
run .every two or 
three days, so you 
have plan accord- 
ingly* If you miss 
one It could wreck 
the rest of your schedule. 

Further details were available by filling In 
your name, address, and phone number In an 
on-line form, so we did this, A few days later 
we were surprised to receive a phone call (yes, 
they phoned us!) from Leisure Rail. AmTrak's 
UK agent. AmTrak had informed them that we 
were interested In USA rail passes, so were 
calling to see how they could help. In fact they 
were extremely helpful over the following few 
weeks, advising on the beat rail pass for our 
purposes, answering all our questions about 
USA rail travel, and sorting out the ticketing 
and payment details in an efficient and 
friendly manner, This was excellent customer 
service - and it was all triggered via the 
Internet 

Throughout the planning period there were 
e-mail messages zooming back and forth be- 
tween John. jTir,, pur Texan friends, and 
ourselves, confirming all the arrangements. 
One day a message arrived from John that 
caused a little consternation. Neither he nor 
his wife Alison would be able to meet us at 
Chicago's Union Station as originally plan- 
ned. They suggested we travelled the 2S miles 
out to Wheaton on a Chicago district commu- 
ter train and take a taxi from the station to 
their apartment and they'd meet us there. So, 
52 



All the information you will need to ride 
Metra 's Commuter Rail System 

Servini Nwihtatt lllineiT 



m*iiM*^i*'JN;.Jj7.j-'jijJ;^'i,.|. : J.'i;j'iJ,J;j.'J'!':jj:. jji:.v;i , J.-J.-J-j-;.J,-.iijjwi(ii» , *i«i'f*inij| 



ornution 



'Americans With UkaMlfflrc lafWIMftHfllL 



J.;.., JJ ii) J y j! .j)H3; ; Aiii?. ! .i.»ii; 



••—*■>■>?■■ 



^j% 



ft was back to Yahoo again where we found a 
web- site containing route maps and the com- 
plete current timetable for Mctra Rail 
{www.mfitrarail.com). Chicago's local train 
system! Details of the Chicago-Wheaton ser- 
vice were duly added to our growing collection 
of travel documentation. 



SOMEWHERE 
TO STAY 

Accommodation was the next area to tackle, 
to cover our now somewhat btzamc looking 
Itinerary. We'd need a hotel somewhere In the 
DFW area for a couple of nights at the start of 
our visit, another for six nights on our return 
to Fort Worth, and one In Houston for our 
final night. In Chicago we'd be staying with 
John and Alison, so no hotel needed there. 
Many years ago I had a business trip to Fort 
Worth and stayed at great hotel, the Worth! n- 
gton, for a ridiculously cheap price (about £50 
for a large, executive suite). So we looked it 
up on Yahoo and sure enough, it has its own 
web-site. The best room deal listed there was 
now a wallet-busting £ 1 60 per night, so we 







decided to check out Holiday Inn 
prices instead. There are Holiday 
Inns all around the DFW area, so 
via their web -site (www. holiday- 
inn .com) we priced several for 
comparison purposes and even- 
tual ly settled on one that suited 
our budget. 

You can also cheek availability 
of Holiday Inn rooms on-line for 
the dates and type of room you 
want. To our chagrin we disco- 
vered that our first choice hotel 
was fully booked. Number two on 
our list had rooms available, so 
we went for that. Again wc could 
have booked on-line, but the cre- 
dit card number paranoia set in 
once more and we called the free 
Holiday Inn reservation number 
instead. The person taking the 
booking tried to charge us a 
higher room rate than we were 
expecting, but relented when 1 
quoted the rate we'd seen on the 
web- site. We booked the hotel for 
Houston at the same time, and 
got the web -site rate for that too. 

We decided to wait and see how 
much cash wc had left at the end 
of our Chicago stay before booking accommo- 
dation for the return visit to Fort Worth. In 
fact, our Texan friends found a really good 
deal for us, and this was sorted out via e-mail 
before we left Chicago, 

The only other essential to take care of was 
the car hire, but as we were staying near the 
airport we figured wc could get a good deal 
locally when we arrived, and this proved to be 
the ease. But you can look up rental rates 
and/or book on-line with the major com- 
panies if you wish. 




ISMSmSS 



m. 






Adler Planetarium & Astronomy Museum 

liilfrpre ting the Exploration of Ike Univtru 



ID'dL« U <fc* A*n PI. 



aflEJWHWgaw 



TOURIST 
ATTRACTIONS 



Page 6*s New Atari User 



After sorting out all the essentials we started 
checking out tourist attractions, using the 
Yahoo and AltaVista (www.altavista.digital- 
.oOftl) search engines, We (bund dozens of 
intriguing possibilities here - in Fort Worth 
there's Billy Bobs (wWW.bll1ybobstexas.com), 
the biggest bar and night-club In the world 

Page 6's New Atari User 53 




contact ... contact ... contact 



(accommodating 6000 people and with live 
bull-riding competitions on certain nlghtst}: 
the Stockyards (www,stockyardsstatiori.corn) r 
which Is surely one of Texas's great undisco- 
vered tourist attractions with its terrific res- 
taurants, bars, rodeo arena, shops; etc.; and 
the Tarantula (www.Gkgrapevine.tx.Lis/trairi/ 
tarantula.html), a restored wild-west steam 
train that operates excursions from the 
Stockyards several times a week. For Chicago 
we checked out what was on at the many 
theatres, and Jazz and blues clubs; details of 
the excellent Museum of Science and Indus- 
try (www.msichicago.corn); the Museum of 
Contemporary Art (www.mcachicago.com}: 
and the Adlcr Planetarium (astCO.UChiea- 



go.edu/adier). 

Thanks to the Internet wc were able to do 
virtually all the research for this trip from 
home. If we wished wc could also have made 
on-line reservations and payment for air 
travel, hotels, and car hire. During the trip. 
everything turned out pretty well as our Inter- 
net research had shown - even the Chicago 
Metra Rail commuter train we caught depar- 
ted at the time stated on the Internet timet- 
able. Overall, our experience backed up John 
Jnr's. findings - that the Internet really Is a 
usable, practical tool for this sort of activity. 
So. If you need to plan a trip, give it a try - 
you'll be amazed at the useful facilities and 
material out there. * 



NAU Internet Contact List 

The following NAU reactors would welcome e mail contact Iron other Atari users, if you'd like to 
be added to this list please drop an e-mail nets to John S Davison at the address below 



Daniel Baverstock 
Paul Bramley 
Paul Carlson 
Johnny Chan 
Kevin Cooke 
Michael Current 
John S Davison 
Damian Dixon 
Gary Dundas 
Derek Fern 
Dean Garraghty 
Joel Goodwin 
Paul Herbert 
Gordon Hooper 
Fred Meijer 
Ann O'Driscoll 
Allan Palmer 
Paul Rixon 
Paulo A Rodrigues 
Brad Rogers 
Nigel Tuiion 
Henning Wright 
Daniel Ye I land 
Bryan Zillwood 



d ba ver stocked m istra 1 .00 , uk 

p. bramley@student.qut.edu.au 

paul.carlson@hn.se 

jwc han@clara.net 

k ji-coo Ke@wpg .uwe.ac.uk 

mcu rrent@carieton.edu 

|ohn_dav iso n@cornpu s erve .com 

damian@tenet.co.uk 

da vadar@ hotkey . net .au 

101755. 2443@compu se rv a . co m 

dgs@clara.net 

jgoodw in@wilco.co.uk 

1 47378.97@swansea.ac.uk 

ua5S8@freenet.victoriabc.ca 

fmeijer@dsv.nl 

annod@iol.ie 

Allan_Palmer&bigfoot,com 

rixo np. ra iltrack@e ms .rail- co . u k 

nop25450@ mail.telepac.pt 

b rad@ piano sa .d e mo n . co . u k 

npturto n@msn.com 

kofta@algonet.se 

yh 1 82530@stmaiLstaffs.ac.uk 

b4.zillw00d@exeter.ac.uk 



jrOR SALE 



800/400 SYSTEMS: 800XL 
computer, 1050 disk drive, 1010 
program recorder. 400 "Mapllns' 
48K upgrade, 410 program recor- 
der, power supplies, leads, manu- 
als, joys ticks/ paddles, ROMs, 
disks, tapes, magazines 1981 to 
present day. Excellent condition - 
in storage for several years. £100. 
No splits, no offers, buyer collects. 
Contact S. Campbell on 01753 
536707 (Slough, Berks) 

LOTS OF STUFF: Atari 8-bit 
hardware & software. For list 
please contact Mike on (01302) 
834410 or e-mail hamster@global- 
net.co.uk 



FOR SALE 



SURPLUS HARDWARE: 8-bit 
hardware for sale, surplus to 
needs - 800's, 800 & 600XL's. 65 & 
130XE's and 1050 disk drives with 
and without US Doublers, plus 
other odds and ends. Please tele- 
phone Richard for an up to date 
list on 01202 256927 



WA2VTEO 



ROM CARTRIDGES: ROMs for 
Atari XL/XE wanted, boxed with 
instructions preferred. Also origin- 
al copy of LEADERBOARD for Atari 
ST/E. Call Chris on 0049 2 163 
990329 (Germany) 



FREE TO SUBSCRIBERS 

The CONTACT column la free of charge la subscribers who wish to sell their 
equipment or contact other readers. Space is limited so we request that entries be 
kept as short as possible. Extremely long entries may be heavily edited or Ignored . 
Send your CONTACT notice on a separate sheet of paper [not as part of a letter) to: 

CONTACT, PAGE 6 PUBLISHING, P.O. BOX 54, STAFFORD, ST16 1DR 



FOR SALE ... WANTED ... PEN PALS ... ADVICE ... HELP 



54 



Page 6's New Atari User 



Certain program listings which are too long to include in the magazine may be obtained 
free of charge as printed listings to type In. All programs are, however. Included on the 
Issue Disk which is available with each Issue. Remember this disk also Includes BONUS 
PROGRAMS which do not appear in the magazine. If you would like the type-In listings 
please write or telephone indicating which listings you require. Please note that there 
are not necessarily extra listings for every magazine. 

Write to HSTINGS, NEW ATARI USER, P.O. BOX 54, 
STAFFORD, ST1B 1DR or telephone Ol 785 241153 

Page 6's New Atari User